1220123100 has 288 divisors, whose sum is σ = 4255727616. Its totient is φ = 264038400.

The previous prime is 1220123083. The next prime is 1220123111. The reversal of 1220123100 is 13210221.

It is a super-2 number, since 2×1220123100² = 2977400758307220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3185509 + ... + 3185891.

It is an arithmetic number, because the mean of its divisors is an integer number (14776832).

Almost surely, 2^1220123100 is an apocalyptic number.

1220123100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1220123100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2127863808).

1220123100 is an abundant number, since it is smaller than the sum of its proper divisors (3035604516).

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

1220123100 is a wasteful number, since it uses less digits than its factorization.

1220123100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485 (or 478 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 1220123100 is about 34930.2605200706. The cubic root of 1220123100 is about 1068.5656677407.

Adding to 1220123100 its reverse (13210221), we get a palindrome (1233333321).

The spelling of 1220123100 in words is "one billion, two hundred twenty million, one hundred twenty-three thousand, one hundred".