999688645 has 16 divisors (see below), whose sum is σ = 1227912192. Its totient is φ = 781107840.

The previous prime is 999688643. The next prime is 999688649. The reversal of 999688645 is 546886999.

999688645 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 999688645 - 2¹ = 999688643 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 (999688643) 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, 24300 + ... + 50890.

It is an arithmetic number, because the mean of its divisors is an integer number (76744512).

Almost surely, 2^999688645 is an apocalyptic number.

It is an amenable number.

999688645 is a deficient number, since it is larger than the sum of its proper divisors (228223547).

999688645 is a wasteful number, since it uses less digits than its factorization.

999688645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26772.

The product of its digits is 33592320, while the sum is 64.

The square root of 999688645 is about 31617.8532636231. The cubic root of 999688645 is about 999.8962042268.

The spelling of 999688645 in words is "nine hundred ninety-nine million, six hundred eighty-eight thousand, six hundred forty-five".