400641686 has 16 divisors (see below), whose sum is σ = 637314480. Its totient is φ = 188240640.

The previous prime is 400641679. The next prime is 400641691. The reversal of 400641686 is 686146004.

It is a congruent number.

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, 13466 + ... + 31346.

It is an arithmetic number, because the mean of its divisors is an integer number (39832155).

Almost surely, 2^400641686 is an apocalyptic number.

400641686 is a deficient number, since it is larger than the sum of its proper divisors (236672794).

400641686 is a wasteful number, since it uses less digits than its factorization.

400641686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18559.

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 400641686 is about 20016.0357213910. The cubic root of 400641686 is about 737.2000878022.

The spelling of 400641686 in words is "four hundred million, six hundred forty-one thousand, six hundred eighty-six".