400637420 has 24 divisors (see below), whose sum is σ = 885620400. Its totient is φ = 151820352.

The previous prime is 400637417. The next prime is 400637449. The reversal of 400637420 is 24736004.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 400637420.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 526775 + ... + 527534.

It is an arithmetic number, because the mean of its divisors is an integer number (36900850).

Almost surely, 2^400637420 is an apocalyptic number.

It is an amenable number.

400637420 is an abundant number, since it is smaller than the sum of its proper divisors (484982980).

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

400637420 is a wasteful number, since it uses less digits than its factorization.

400637420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1054337 (or 1054335 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 26.

The square root of 400637420 is about 20015.9291565493. The cubic root of 400637420 is about 737.1974712441.

The spelling of 400637420 in words is "four hundred million, six hundred thirty-seven thousand, four hundred twenty".