397637280 has 72 divisors (see below), whose sum is σ = 1356942132. Its totient is φ = 106036224.

The previous prime is 397637267. The next prime is 397637281. The reversal of 397637280 is 82736793.

It is a happy number.

397637280 is a `hidden beast` number, since 3 + 9 + 7 + 637 + 2 + 8 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 324432144 + 73205136 = 18012^2 + 8556^2 .

It is a tau number, because it is divible by the number of its divisors (72).

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

It is not an unprimeable number, because it can be changed into a prime (397637281) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 136629 + ... + 139508.

Almost surely, 2^397637280 is an apocalyptic number.

397637280 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

397637280 is an abundant number, since it is smaller than the sum of its proper divisors (959304852).

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

397637280 is a wasteful number, since it uses less digits than its factorization.

397637280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276158 (or 276147 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The square root of 397637280 is about 19940.8445157170. The cubic root of 397637280 is about 735.3527114580.

The spelling of 397637280 in words is "three hundred ninety-seven million, six hundred thirty-seven thousand, two hundred eighty".