399781098 has 24 divisors (see below), whose sum is σ = 866708388. Its totient is φ = 133180992.

The previous prime is 399781087. The next prime is 399781099. The reversal of 399781098 is 890187993.

It can be written as a sum of positive squares in 2 ways, for example, as 399080529 + 700569 = 19977^2 + 837^2 .

It is not an unprimeable number, because it can be changed into a prime (399781099) 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, 29886 + ... + 41142.

Almost surely, 2^399781098 is an apocalyptic number.

399781098 is an abundant number, since it is smaller than the sum of its proper divisors (466927290).

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

399781098 is a wasteful number, since it uses less digits than its factorization.

399781098 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13238 (or 13235 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 54.

The square root of 399781098 is about 19994.5267010750. The cubic root of 399781098 is about 736.6718682251.

The spelling of 399781098 in words is "three hundred ninety-nine million, seven hundred eighty-one thousand, ninety-eight".