399021838455 has 16 divisors (see below), whose sum is σ = 666192983040. Its totient is φ = 203558966688.

The previous prime is 399021838379. The next prime is 399021838459. The reversal of 399021838455 is 554838120993.

It is a happy number.

It is not a de Polignac number, because 399021838455 - 2¹² = 399021834359 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 399021838395 and 399021838404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399021838459) 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, 578292175 + ... + 578292864.

It is an arithmetic number, because the mean of its divisors is an integer number (41637061440).

Almost surely, 2^399021838455 is an apocalyptic number.

399021838455 is a deficient number, since it is larger than the sum of its proper divisors (267171144585).

399021838455 is a wasteful number, since it uses less digits than its factorization.

399021838455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1156585070.

The product of its (nonzero) digits is 9331200, while the sum is 57.

The spelling of 399021838455 in words is "three hundred ninety-nine billion, twenty-one million, eight hundred thirty-eight thousand, four hundred fifty-five".