396740640 has 192 divisors, whose sum is σ = 1303102080. Its totient is φ = 101376000.

The previous prime is 396740633. The next prime is 396740651. The reversal of 396740640 is 46047693.

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, 1580515 + ... + 1580765.

It is an arithmetic number, because the mean of its divisors is an integer number (6786990).

Almost surely, 2^396740640 is an apocalyptic number.

396740640 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 396740640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (651551040).

396740640 is an abundant number, since it is smaller than the sum of its proper divisors (906361440).

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

396740640 is a wasteful number, since it uses less digits than its factorization.

396740640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395 (or 387 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 39.

The square root of 396740640 is about 19918.3493291989. The cubic root of 396740640 is about 734.7995751356.

The spelling of 396740640 in words is "three hundred ninety-six million, seven hundred forty thousand, six hundred forty".