100491043021 has 2 divisors, whose sum is σ = 100491043022. Its totient is φ = 100491043020.

The previous prime is 100491042983. The next prime is 100491043039. The reversal of 100491043021 is 120340194001.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 96267472900 + 4223570121 = 310270^2 + 64989^2 .

It is a cyclic number.

It is not a de Polignac number, because 100491043021 - 2²⁷ = 100356825293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100491043321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50245521510 + 50245521511.

It is an arithmetic number, because the mean of its divisors is an integer number (50245521511).

Almost surely, 2^100491043021 is an apocalyptic number.

It is an amenable number.

100491043021 is a deficient number, since it is larger than the sum of its proper divisors (1).

100491043021 is an equidigital number, since it uses as much as digits as its factorization.

100491043021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 25.

The spelling of 100491043021 in words is "one hundred billion, four hundred ninety-one million, forty-three thousand, twenty-one".