399446692621 has 16 divisors (see below), whose sum is σ = 403872900480. Its totient is φ = 395049695040.

The previous prime is 399446692583. The next prime is 399446692627. The reversal of 399446692621 is 126296644993.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399446692621 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 399446692621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399446692627) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28128895 + ... + 28143091.

It is an arithmetic number, because the mean of its divisors is an integer number (25242056280).

Almost surely, 2^399446692621 is an apocalyptic number.

It is an amenable number.

399446692621 is a deficient number, since it is larger than the sum of its proper divisors (4426207859).

399446692621 is a wasteful number, since it uses less digits than its factorization.

399446692621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15204.

The product of its digits is 30233088, while the sum is 61.

The spelling of 399446692621 in words is "three hundred ninety-nine billion, four hundred forty-six million, six hundred ninety-two thousand, six hundred twenty-one".