397956840 has 64 divisors (see below), whose sum is σ = 1195214400. Its totient is φ = 106002432.

The previous prime is 397956773. The next prime is 397956841. The reversal of 397956840 is 48659793.

It is not an unprimeable number, because it can be changed into a prime (397956841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 173944 + ... + 176216.

It is an arithmetic number, because the mean of its divisors is an integer number (18675225).

Almost surely, 2^397956840 is an apocalyptic number.

397956840 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

397956840 is an abundant number, since it is smaller than the sum of its proper divisors (797257560).

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

397956840 is a wasteful number, since it uses less digits than its factorization.

397956840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3746 (or 3742 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 51.

The square root of 397956840 is about 19948.8556062748. The cubic root of 397956840 is about 735.5496467077.

The spelling of 397956840 in words is "three hundred ninety-seven million, nine hundred fifty-six thousand, eight hundred forty".