400389161 has 2 divisors, whose sum is σ = 400389162. Its totient is φ = 400389160.

The previous prime is 400389137. The next prime is 400389181. The reversal of 400389161 is 161983004.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 397603600 + 2785561 = 19940^2 + 1669^2 .

It is a cyclic number.

It is not a de Polignac number, because 400389161 - 2⁶ = 400389097 is a prime.

It is a super-2 number, since 2×400389161² = 320622960492567842, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (400389181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200194580 + 200194581.

It is an arithmetic number, because the mean of its divisors is an integer number (200194581).

Almost surely, 2^400389161 is an apocalyptic number.

It is an amenable number.

400389161 is a deficient number, since it is larger than the sum of its proper divisors (1).

400389161 is an equidigital number, since it uses as much as digits as its factorization.

400389161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 400389161 is about 20009.7266598022. The cubic root of 400389161 is about 737.0451691763.

The spelling of 400389161 in words is "four hundred million, three hundred eighty-nine thousand, one hundred sixty-one".