689615731 has 16 divisors (see below), whose sum is σ = 813333760. Its totient is φ = 572352480.

The previous prime is 689615713. The next prime is 689615767. The reversal of 689615731 is 137516986.

It is a happy number.

It is not a de Polignac number, because 689615731 - 2⁹ = 689615219 is a prime.

It is a super-2 number, since 2×689615731² = 951139712885328722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (689615131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48340 + ... + 60958.

It is an arithmetic number, because the mean of its divisors is an integer number (50833360).

Almost surely, 2^689615731 is an apocalyptic number.

689615731 is a deficient number, since it is larger than the sum of its proper divisors (123718029).

689615731 is a wasteful number, since it uses less digits than its factorization.

689615731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12874.

The product of its digits is 272160, while the sum is 46.

The square root of 689615731 is about 26260.5356190615. The cubic root of 689615731 is about 883.4915224309.

The spelling of 689615731 in words is "six hundred eighty-nine million, six hundred fifteen thousand, seven hundred thirty-one".