309728880 has 160 divisors (see below), whose sum is σ = 1123142400. Its totient is φ = 78236928.

The previous prime is 309728863. The next prime is 309728897. The reversal of 309728880 is 88827903.

It is an interprime number because it is at equal distance from previous prime (309728863) and next prime (309728897).

It is a super-3 number, since 3×309728880³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37267 + ... + 44813.

It is an arithmetic number, because the mean of its divisors is an integer number (7019640).

Almost surely, 2^309728880 is an apocalyptic number.

309728880 is a gapful number since it is divisible by the number (30) 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 309728880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (561571200).

309728880 is an abundant number, since it is smaller than the sum of its proper divisors (813413520).

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

309728880 is a wasteful number, since it uses less digits than its factorization.

309728880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7588 (or 7576 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 309728880 is about 17599.1158868848. The cubic root of 309728880 is about 676.5925852015.

The spelling of 309728880 in words is "three hundred nine million, seven hundred twenty-eight thousand, eight hundred eighty".