405864468509 has 2 divisors, whose sum is σ = 405864468510. Its totient is φ = 405864468508.

The previous prime is 405864468487. The next prime is 405864468547. The reversal of 405864468509 is 905864468504.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 249622142884 + 156242325625 = 499622^2 + 395275^2 .

It is a cyclic number.

It is not a de Polignac number, because 405864468509 - 2²⁰ = 405863419933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405864668509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202932234254 + 202932234255.

It is an arithmetic number, because the mean of its divisors is an integer number (202932234255).

Almost surely, 2^405864468509 is an apocalyptic number.

It is an amenable number.

405864468509 is a deficient number, since it is larger than the sum of its proper divisors (1).

405864468509 is an equidigital number, since it uses as much as digits as its factorization.

405864468509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 33177600, while the sum is 59.

The spelling of 405864468509 in words is "four hundred five billion, eight hundred sixty-four million, four hundred sixty-eight thousand, five hundred nine".