1220387280 has 320 divisors, whose sum is σ = 4600419840. Its totient is φ = 261660672.

The previous prime is 1220387249. The next prime is 1220387303. The reversal of 1220387280 is 827830221.

It is a super-2 number, since 2×1220387280² = 2978690226371596800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1802302 + ... + 1802978.

It is an arithmetic number, because the mean of its divisors is an integer number (14376312).

Almost surely, 2^1220387280 is an apocalyptic number.

1220387280 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 1220387280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2300209920).

1220387280 is an abundant number, since it is smaller than the sum of its proper divisors (3380032560).

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

1220387280 is a wasteful number, since it uses less digits than its factorization.

1220387280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 766 (or 760 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 1220387280 is about 34934.0418503213. The cubic root of 1220387280 is about 1068.6427838138.

The spelling of 1220387280 in words is "one billion, two hundred twenty million, three hundred eighty-seven thousand, two hundred eighty".