100172805 has 24 divisors (see below), whose sum is σ = 162016608. Its totient is φ = 52851456.

The previous prime is 100172777. The next prime is 100172827. The reversal of 100172805 is 508271001.

It is not a de Polignac number, because 100172805 - 2⁶ = 100172741 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 191274 + ... + 191796.

It is an arithmetic number, because the mean of its divisors is an integer number (6750692).

Almost surely, 2^100172805 is an apocalyptic number.

100172805 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

100172805 is a deficient number, since it is larger than the sum of its proper divisors (61843803).

100172805 is an equidigital number, since it uses as much as digits as its factorization.

100172805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 757 (or 644 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 24.

The square root of 100172805 is about 10008.6365205257. The cubic root of 100172805 is about 464.4260927561.

The spelling of 100172805 in words is "one hundred million, one hundred seventy-two thousand, eight hundred five".