400166538 has 16 divisors (see below), whose sum is σ = 826150656. Its totient is φ = 129085920.

The previous prime is 400166491. The next prime is 400166593. The reversal of 400166538 is 835661004.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 400166499 and 400166508.

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, 1075531 + ... + 1075902.

It is an arithmetic number, because the mean of its divisors is an integer number (51634416).

Almost surely, 2^400166538 is an apocalyptic number.

400166538 is an abundant number, since it is smaller than the sum of its proper divisors (425984118).

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

400166538 is a wasteful number, since it uses less digits than its factorization.

400166538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2151469.

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 400166538 is about 20004.1630167323. The cubic root of 400166538 is about 736.9085407465.

The spelling of 400166538 in words is "four hundred million, one hundred sixty-six thousand, five hundred thirty-eight".