690812639 has 4 divisors (see below), whose sum is σ = 753613800. Its totient is φ = 628011480.

The previous prime is 690812623. The next prime is 690812677. The reversal of 690812639 is 936218096.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 690812639 - 2⁴ = 690812623 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 690812639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (690812699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31400564 + ... + 31400585.

It is an arithmetic number, because the mean of its divisors is an integer number (188403450).

Almost surely, 2^690812639 is an apocalyptic number.

690812639 is a deficient number, since it is larger than the sum of its proper divisors (62801161).

690812639 is a wasteful number, since it uses less digits than its factorization.

690812639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62801160.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 690812639 is about 26283.3148404078. The cubic root of 690812639 is about 884.0023609712.

The spelling of 690812639 in words is "six hundred ninety million, eight hundred twelve thousand, six hundred thirty-nine".