400665697 has 2 divisors, whose sum is σ = 400665698. Its totient is φ = 400665696.

The previous prime is 400665691. The next prime is 400665719. The reversal of 400665697 is 796566004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 275427216 + 125238481 = 16596^2 + 11191^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400665697 is a prime.

It is not a weakly prime, because it can be changed into another prime (400665691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200332848 + 200332849.

It is an arithmetic number, because the mean of its divisors is an integer number (200332849).

Almost surely, 2^400665697 is an apocalyptic number.

It is an amenable number.

400665697 is a deficient number, since it is larger than the sum of its proper divisors (1).

400665697 is an equidigital number, since it uses as much as digits as its factorization.

400665697 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 272160, while the sum is 43.

The square root of 400665697 is about 20016.6355064981. The cubic root of 400665697 is about 737.2148146420.

The spelling of 400665697 in words is "four hundred million, six hundred sixty-five thousand, six hundred ninety-seven".