399789738 has 24 divisors (see below), whose sum is σ = 866745828. Its totient is φ = 133180992.

The previous prime is 399789727. The next prime is 399789739. The reversal of 399789738 is 837987993.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 356190129 + 43599609 = 18873^2 + 6603^2 .

It is a super-2 number, since 2×399789738² = 319663669220217288, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (399789739) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27870 + ... + 39702.

Almost surely, 2^399789738 is an apocalyptic number.

399789738 is an abundant number, since it is smaller than the sum of its proper divisors (466956090).

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

399789738 is a wasteful number, since it uses less digits than its factorization.

399789738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13718 (or 13715 counting only the distinct ones).

The product of its digits is 20575296, while the sum is 63.

The square root of 399789738 is about 19994.7427590354. The cubic root of 399789738 is about 736.6771751286.

The spelling of 399789738 in words is "three hundred ninety-nine million, seven hundred eighty-nine thousand, seven hundred thirty-eight".