100721905817 has 8 divisors (see below), whose sum is σ = 108557877120. Its totient is φ = 92898524880.

The previous prime is 100721905799. The next prime is 100721905897. The reversal of 100721905817 is 718509127001.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 100721905817 - 2³² = 96426938521 is a prime.

It is a super-2 number, since 2×100721905817² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100721905897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3130967 + ... + 3162972.

It is an arithmetic number, because the mean of its divisors is an integer number (13569734640).

Almost surely, 2^100721905817 is an apocalyptic number.

It is an amenable number.

100721905817 is a deficient number, since it is larger than the sum of its proper divisors (7835971303).

100721905817 is a wasteful number, since it uses less digits than its factorization.

100721905817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6295183.

The product of its (nonzero) digits is 35280, while the sum is 41.

The spelling of 100721905817 in words is "one hundred billion, seven hundred twenty-one million, nine hundred five thousand, eight hundred seventeen".