396999521 has 16 divisors (see below), whose sum is σ = 438286464. Its totient is φ = 358036224.

The previous prime is 396999479. The next prime is 396999557. The reversal of 396999521 is 125999693.

It is a cyclic number.

It is not a de Polignac number, because 396999521 - 2⁶ = 396999457 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (396999571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33620 + ... + 43866.

It is an arithmetic number, because the mean of its divisors is an integer number (27392904).

Almost surely, 2^396999521 is an apocalyptic number.

It is an amenable number.

396999521 is a deficient number, since it is larger than the sum of its proper divisors (41286943).

396999521 is a wasteful number, since it uses less digits than its factorization.

396999521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10360.

The product of its digits is 1180980, while the sum is 53.

The square root of 396999521 is about 19924.8468250072. The cubic root of 396999521 is about 734.9593640668.

The spelling of 396999521 in words is "three hundred ninety-six million, nine hundred ninety-nine thousand, five hundred twenty-one".