400552531 has 2 divisors, whose sum is σ = 400552532. Its totient is φ = 400552530.

The previous prime is 400552513. The next prime is 400552561. The reversal of 400552531 is 135255004.

Together with previous prime (400552513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 400552531 - 2¹¹ = 400550483 is a prime.

It is a super-2 number, since 2×400552531² = 320884660181011922, which contains 22 as substring.

It is equal to p_21364144 and since 400552531 and 21364144 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 400552496 and 400552505.

It is not a weakly prime, because it can be changed into another prime (400552511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200276265 + 200276266.

It is an arithmetic number, because the mean of its divisors is an integer number (200276266).

Almost surely, 2^400552531 is an apocalyptic number.

400552531 is a deficient number, since it is larger than the sum of its proper divisors (1).

400552531 is an equidigital number, since it uses as much as digits as its factorization.

400552531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 400552531 is about 20013.8085081276. The cubic root of 400552531 is about 737.1454005742.

The spelling of 400552531 in words is "four hundred million, five hundred fifty-two thousand, five hundred thirty-one".