1220155300 has 144 divisors (see below), whose sum is σ = 3430752640. Its totient is φ = 365783040.

The previous prime is 1220155289. The next prime is 1220155301. The reversal of 1220155300 is 35510221.

1220155300 is a nontrivial binomial coefficient, being equal to C(49400, 2).

It is a super-2 number, since 2×1220155300² = 2977557912236180000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is not an unprimeable number, because it can be changed into a prime (1220155301) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 169372 + ... + 176428.

Almost surely, 2^1220155300 is an apocalyptic number.

1220155300 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1220155300 is the 49399-th triangular number and also the 24700-th hexagonal number.

1220155300 is the 16467-th centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1220155300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1715376320).

1220155300 is an abundant number, since it is smaller than the sum of its proper divisors (2210597340).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1220155300 is a wasteful number, since it uses less digits than its factorization.

1220155300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7110 (or 7103 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 1220155300 is about 34930.7214354356. The cubic root of 1220155300 is about 1068.5750677517.

Adding to 1220155300 its reverse (35510221), we get a palindrome (1255665521).

It can be divided in two parts, 1220 and 155300, that added together give a triangular number (156520 = T₅₅₉).

The spelling of 1220155300 in words is "one billion, two hundred twenty million, one hundred fifty-five thousand, three hundred".