396405969 has 8 divisors (see below), whose sum is σ = 536430240. Its totient is φ = 260326176.

The previous prime is 396405967. The next prime is 396405973. The reversal of 396405969 is 969504693.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 396405969 - 2¹ = 396405967 is a prime.

It is a super-2 number, since 2×396405969² = 314275384517657922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (396405967) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 985884 + ... + 986285.

It is an arithmetic number, because the mean of its divisors is an integer number (67053780).

Almost surely, 2^396405969 is an apocalyptic number.

It is an amenable number.

396405969 is a deficient number, since it is larger than the sum of its proper divisors (140024271).

396405969 is a wasteful number, since it uses less digits than its factorization.

396405969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1972239.

The product of its (nonzero) digits is 1574640, while the sum is 51.

The square root of 396405969 is about 19909.9464841069. The cubic root of 396405969 is about 734.5929033507.

The spelling of 396405969 in words is "three hundred ninety-six million, four hundred five thousand, nine hundred sixty-nine".