405663939 has 6 divisors (see below), whose sum is σ = 585959036. Its totient is φ = 270442620.

The previous prime is 405663917. The next prime is 405663953. The reversal of 405663939 is 939366504.

It is a happy number.

405663939 is a `hidden beast` number, since 4 + 0 + 5 + 6 + 639 + 3 + 9 = 666.

It is not a de Polignac number, because 405663939 - 2²³ = 397275331 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 405663894 and 405663903.

It is not an unprimeable number, because it can be changed into a prime (405663239) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22536877 + ... + 22536894.

Almost surely, 2^405663939 is an apocalyptic number.

405663939 is a deficient number, since it is larger than the sum of its proper divisors (180295097).

405663939 is a wasteful number, since it uses less digits than its factorization.

405663939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45073777 (or 45073774 counting only the distinct ones).

The product of its (nonzero) digits is 524880, while the sum is 45.

The square root of 405663939 is about 20141.1007395326. The cubic root of 405663939 is about 740.2677014163.

The spelling of 405663939 in words is "four hundred five million, six hundred sixty-three thousand, nine hundred thirty-nine".