405911969 has 2 divisors, whose sum is σ = 405911970. Its totient is φ = 405911968.

The previous prime is 405911911. The next prime is 405911971. The reversal of 405911969 is 969119504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 266081344 + 139830625 = 16312^2 + 11825^2 .

It is a cyclic number.

It is not a de Polignac number, because 405911969 - 2⁸ = 405911713 is a prime.

It is a super-2 number, since 2×405911969² = 329529053154913922, which contains 22 as substring.

Together with 405911971, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (405941969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202955984 + 202955985.

It is an arithmetic number, because the mean of its divisors is an integer number (202955985).

Almost surely, 2^405911969 is an apocalyptic number.

It is an amenable number.

405911969 is a deficient number, since it is larger than the sum of its proper divisors (1).

405911969 is an equidigital number, since it uses as much as digits as its factorization.

405911969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 87480, while the sum is 44.

The square root of 405911969 is about 20147.2571085992. The cubic root of 405911969 is about 740.4185415350.

The spelling of 405911969 in words is "four hundred five million, nine hundred eleven thousand, nine hundred sixty-nine".