400921957 has 2 divisors, whose sum is σ = 400921958. Its totient is φ = 400921956.

The previous prime is 400921943. The next prime is 400921991. The reversal of 400921957 is 759129004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 336135556 + 64786401 = 18334^2 + 8049^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400921957 is a prime.

It is a super-3 number, since 3×400921957³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400921057) 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, 200460978 + 200460979.

It is an arithmetic number, because the mean of its divisors is an integer number (200460979).

Almost surely, 2^400921957 is an apocalyptic number.

It is an amenable number.

400921957 is a deficient number, since it is larger than the sum of its proper divisors (1).

400921957 is an equidigital number, since it uses as much as digits as its factorization.

400921957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22680, while the sum is 37.

The square root of 400921957 is about 20023.0356589604. The cubic root of 400921957 is about 737.3719517994.

The spelling of 400921957 in words is "four hundred million, nine hundred twenty-one thousand, nine hundred fifty-seven".