405431491 has 2 divisors, whose sum is σ = 405431492. Its totient is φ = 405431490.

The previous prime is 405431479. The next prime is 405431549. The reversal of 405431491 is 194134504.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 405431491 - 2⁷ = 405431363 is a prime.

It is not a weakly prime, because it can be changed into another prime (405431431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202715745 + 202715746.

It is an arithmetic number, because the mean of its divisors is an integer number (202715746).

Almost surely, 2^405431491 is an apocalyptic number.

405431491 is a deficient number, since it is larger than the sum of its proper divisors (1).

405431491 is an equidigital number, since it uses as much as digits as its factorization.

405431491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 405431491 is about 20135.3294236772. The cubic root of 405431491 is about 740.1262817114.

Adding to 405431491 its reverse (194134504), we get a palindrome (599565995).

The spelling of 405431491 in words is "four hundred five million, four hundred thirty-one thousand, four hundred ninety-one".