397232640 has 320 divisors, whose sum is σ = 1614539520. Its totient is φ = 90685440.

The previous prime is 397232623. The next prime is 397232651. The reversal of 397232640 is 46232793.

It is a happy number.

397232640 is a `hidden beast` number, since 3 + 9 + 7 + 2 + 3 + 2 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 397232595 and 397232604.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 483430 + ... + 484250.

It is an arithmetic number, because the mean of its divisors is an integer number (5045436).

Almost surely, 2^397232640 is an apocalyptic number.

397232640 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 397232640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (807269760).

397232640 is an abundant number, since it is smaller than the sum of its proper divisors (1217306880).

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

397232640 is an equidigital number, since it uses as much as digits as its factorization.

397232640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 860 (or 838 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 36.

The square root of 397232640 is about 19930.6959236249. The cubic root of 397232640 is about 735.1031925084.

The spelling of 397232640 in words is "three hundred ninety-seven million, two hundred thirty-two thousand, six hundred forty".