686902989 has 4 divisors (see below), whose sum is σ = 915870656. Its totient is φ = 457935324.

The previous prime is 686902967. The next prime is 686903023. The reversal of 686902989 is 989209686.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 686902989 - 2¹⁹ = 686378701 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 (686902939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 114483829 + ... + 114483834.

It is an arithmetic number, because the mean of its divisors is an integer number (228967664).

Almost surely, 2^686902989 is an apocalyptic number.

It is an amenable number.

686902989 is a deficient number, since it is larger than the sum of its proper divisors (228967667).

686902989 is a wasteful number, since it uses less digits than its factorization.

686902989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228967666.

The product of its (nonzero) digits is 3359232, while the sum is 57.

The square root of 686902989 is about 26208.8341785742. The cubic root of 686902989 is about 882.3315362962.

The spelling of 686902989 in words is "six hundred eighty-six million, nine hundred two thousand, nine hundred eighty-nine".