399823779438 has 48 divisors (see below), whose sum is σ = 870331288320. Its totient is φ = 132652499712.

The previous prime is 399823779391. The next prime is 399823779451. The reversal of 399823779438 is 834977328993.

399823779438 is a `hidden beast` number, since 3 + 9 + 98 + 2 + 37 + 79 + 438 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12057970 + ... + 12091082.

It is an arithmetic number, because the mean of its divisors is an integer number (18131901840).

Almost surely, 2^399823779438 is an apocalyptic number.

399823779438 is an abundant number, since it is smaller than the sum of its proper divisors (470507508882).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

399823779438 is a wasteful number, since it uses less digits than its factorization.

399823779438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36233 (or 36230 counting only the distinct ones).

The product of its digits is 493807104, while the sum is 72.

The spelling of 399823779438 in words is "three hundred ninety-nine billion, eight hundred twenty-three million, seven hundred seventy-nine thousand, four hundred thirty-eight".