400561081 has 2 divisors, whose sum is σ = 400561082. Its totient is φ = 400561080.

The previous prime is 400561061. The next prime is 400561087. The reversal of 400561081 is 180165004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 206209600 + 194351481 = 14360^2 + 13941^2 .

It is a cyclic number.

It is not a de Polignac number, because 400561081 - 2²⁵ = 367006649 is a prime.

It is a super-2 number, since 2×400561081² = 320898359223777122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (400561087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200280540 + 200280541.

It is an arithmetic number, because the mean of its divisors is an integer number (200280541).

Almost surely, 2^400561081 is an apocalyptic number.

It is an amenable number.

400561081 is a deficient number, since it is larger than the sum of its proper divisors (1).

400561081 is an equidigital number, since it uses as much as digits as its factorization.

400561081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 400561081 is about 20014.0221095111. The cubic root of 400561081 is about 737.1506454529.

The spelling of 400561081 in words is "four hundred million, five hundred sixty-one thousand, eighty-one".