100812812621 has 4 divisors (see below), whose sum is σ = 100813447644. Its totient is φ = 100812177600.

The previous prime is 100812812591. The next prime is 100812812629. The reversal of 100812812621 is 126218218001.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 126218218001 = 181 ⋅697338221.

It can be written as a sum of positive squares in 2 ways, for example, as 89790122500 + 11022690121 = 299650^2 + 104989^2 .

It is a cyclic number.

It is not a de Polignac number, because 100812812621 - 2¹⁰ = 100812811597 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 (100812812629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 157781 + ... + 475941.

It is an arithmetic number, because the mean of its divisors is an integer number (25203361911).

Almost surely, 2^100812812621 is an apocalyptic number.

It is an amenable number.

100812812621 is a deficient number, since it is larger than the sum of its proper divisors (635023).

100812812621 is an equidigital number, since it uses as much as digits as its factorization.

100812812621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 635022.

The product of its (nonzero) digits is 3072, while the sum is 32.

The spelling of 100812812621 in words is "one hundred billion, eight hundred twelve million, eight hundred twelve thousand, six hundred twenty-one".