309972 has 24 divisors (see below), whose sum is σ = 779296. Its totient is φ = 95328.

The previous prime is 309937. The next prime is 309977. The reversal of 309972 is 279903.

309972 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309977) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 838 + ... + 1149.

2³⁰⁹⁹⁷² is an apocalyptic number.

It is an amenable number.

309972 is an abundant number, since it is smaller than the sum of its proper divisors (469324).

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

309972 is a wasteful number, since it uses less digits than its factorization.

309972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2007 (or 2005 counting only the distinct ones).

The product of its (nonzero) digits is 3402, while the sum is 30.

The square root of 309972 is about 556.7512909729. The cubic root of 309972 is about 67.6769568126.

The spelling of 309972 in words is "three hundred nine thousand, nine hundred seventy-two".