689139923 has 4 divisors (see below), whose sum is σ = 689197488. Its totient is φ = 689082360.

The previous prime is 689139881. The next prime is 689139949. The reversal of 689139923 is 329931986.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 689139923 - 2⁶ = 689139859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (689139623) 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, 3311 + ... + 37272.

It is an arithmetic number, because the mean of its divisors is an integer number (172299372).

Almost surely, 2^689139923 is an apocalyptic number.

689139923 is a deficient number, since it is larger than the sum of its proper divisors (57565).

689139923 is a wasteful number, since it uses less digits than its factorization.

689139923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57564.

The product of its digits is 629856, while the sum is 50.

The square root of 689139923 is about 26251.4746823869. The cubic root of 689139923 is about 883.2882840995.

The spelling of 689139923 in words is "six hundred eighty-nine million, one hundred thirty-nine thousand, nine hundred twenty-three".