100864809 has 12 divisors (see below), whose sum is σ = 145870452. Its totient is φ = 67161600.

The previous prime is 100864789. The next prime is 100864811. The reversal of 100864809 is 908468001.

It is a happy number.

100864809 is a `hidden beast` number, since 1 + 0 + 0 + 8 + 648 + 0 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 54243225 + 46621584 = 7365^2 + 6828^2 .

It is not a de Polignac number, because 100864809 - 2¹¹ = 100862761 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (100864609) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1569 + ... + 14289.

It is an arithmetic number, because the mean of its divisors is an integer number (12155871).

Almost surely, 2^100864809 is an apocalyptic number.

It is an amenable number.

100864809 is a deficient number, since it is larger than the sum of its proper divisors (45005643).

100864809 is a wasteful number, since it uses less digits than its factorization.

100864809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13608 (or 13605 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 100864809 is about 10043.1473652436. The cubic root of 100864809 is about 465.4930739200.

The spelling of 100864809 in words is "one hundred million, eight hundred sixty-four thousand, eight hundred nine".