400566665 has 16 divisors (see below), whose sum is σ = 519789312. Its totient is φ = 295183104.

The previous prime is 400566619. The next prime is 400566703. The reversal of 400566665 is 566665004.

It is a de Polignac number, because none of the positive numbers 2^k-400566665 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46139 + ... + 54128.

It is an arithmetic number, because the mean of its divisors is an integer number (32486832).

Almost surely, 2^400566665 is an apocalyptic number.

It is an amenable number.

400566665 is a deficient number, since it is larger than the sum of its proper divisors (119222647).

400566665 is a wasteful number, since it uses less digits than its factorization.

400566665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100336.

The product of its (nonzero) digits is 129600, while the sum is 38.

The square root of 400566665 is about 20014.1616112192. The cubic root of 400566665 is about 737.1540708398.

The spelling of 400566665 in words is "four hundred million, five hundred sixty-six thousand, six hundred sixty-five".