398708687 has 6 divisors (see below), whose sum is σ = 431737992. Its totient is φ = 368038632.

The previous prime is 398708621. The next prime is 398708689. The reversal of 398708687 is 786807893.

It is not a de Polignac number, because 398708687 - 2²⁰ = 397660111 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398708689) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1179443 + ... + 1179780.

It is an arithmetic number, because the mean of its divisors is an integer number (71956332).

Almost surely, 2^398708687 is an apocalyptic number.

398708687 is a deficient number, since it is larger than the sum of its proper divisors (33029305).

398708687 is a wasteful number, since it uses less digits than its factorization.

398708687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2359249 (or 2359236 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 56.

The square root of 398708687 is about 19967.6910783395. The cubic root of 398708687 is about 736.0125720275.

The spelling of 398708687 in words is "three hundred ninety-eight million, seven hundred eight thousand, six hundred eighty-seven".