405418921657 has 2 divisors, whose sum is σ = 405418921658. Its totient is φ = 405418921656.

The previous prime is 405418921613. The next prime is 405418921667. The reversal of 405418921657 is 756129814504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 402731121321 + 2687800336 = 634611^2 + 51844^2 .

It is a cyclic number.

It is not a de Polignac number, because 405418921657 - 2⁷ = 405418921529 is a prime.

It is not a weakly prime, because it can be changed into another prime (405418921667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202709460828 + 202709460829.

It is an arithmetic number, because the mean of its divisors is an integer number (202709460829).

Almost surely, 2^405418921657 is an apocalyptic number.

It is an amenable number.

405418921657 is a deficient number, since it is larger than the sum of its proper divisors (1).

405418921657 is an equidigital number, since it uses as much as digits as its factorization.

405418921657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2419200, while the sum is 52.

The spelling of 405418921657 in words is "four hundred five billion, four hundred eighteen million, nine hundred twenty-one thousand, six hundred fifty-seven".