400946111921 has 2 divisors, whose sum is σ = 400946111922. Its totient is φ = 400946111920.

The previous prime is 400946111897. The next prime is 400946112131. The reversal of 400946111921 is 129111649004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 272541423025 + 128404688896 = 522055^2 + 358336^2 .

It is a cyclic number.

It is not a de Polignac number, because 400946111921 - 2³⁴ = 383766242737 is a prime.

It is not a weakly prime, because it can be changed into another prime (400946111021) 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, 200473055960 + 200473055961.

It is an arithmetic number, because the mean of its divisors is an integer number (200473055961).

Almost surely, 2^400946111921 is an apocalyptic number.

It is an amenable number.

400946111921 is a deficient number, since it is larger than the sum of its proper divisors (1).

400946111921 is an equidigital number, since it uses as much as digits as its factorization.

400946111921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 38.

The spelling of 400946111921 in words is "four hundred billion, nine hundred forty-six million, one hundred eleven thousand, nine hundred twenty-one".