397275840 has 392 divisors, whose sum is σ = 1539136368. Its totient is φ = 97044480.

The previous prime is 397275821. The next prime is 397275847. The reversal of 397275840 is 48572793.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397275847) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 3032575 + ... + 3032705.

Almost surely, 2^397275840 is an apocalyptic number.

397275840 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 397275840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (769568184).

397275840 is an abundant number, since it is smaller than the sum of its proper divisors (1141860528).

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

397275840 is a wasteful number, since it uses less digits than its factorization.

397275840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179 (or 154 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The square root of 397275840 is about 19931.7796495948. The cubic root of 397275840 is about 735.1298396194.

The spelling of 397275840 in words is "three hundred ninety-seven million, two hundred seventy-five thousand, eight hundred forty".