399978812 has 6 divisors (see below), whose sum is σ = 699962928. Its totient is φ = 199989404.

The previous prime is 399978781. The next prime is 399978829. The reversal of 399978812 is 218879993.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 49997348 + ... + 49997355.

It is an arithmetic number, because the mean of its divisors is an integer number (116660488).

Almost surely, 2^399978812 is an apocalyptic number.

It is an amenable number.

399978812 is a deficient number, since it is larger than the sum of its proper divisors (299984116).

399978812 is a wasteful number, since it uses less digits than its factorization.

399978812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99994707 (or 99994705 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 56.

The square root of 399978812 is about 19999.4702929853. The cubic root of 399978812 is about 736.7932899551.

The spelling of 399978812 in words is "three hundred ninety-nine million, nine hundred seventy-eight thousand, eight hundred twelve".