100990621 has 2 divisors, whose sum is σ = 100990622. Its totient is φ = 100990620.

The previous prime is 100990601. The next prime is 100990657. The reversal of 100990621 is 126099001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90820900 + 10169721 = 9530^2 + 3189^2 .

It is a cyclic number.

It is not a de Polignac number, because 100990621 - 2¹⁵ = 100957853 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 100990621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100990601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50495310 + 50495311.

It is an arithmetic number, because the mean of its divisors is an integer number (50495311).

Almost surely, 2^100990621 is an apocalyptic number.

It is an amenable number.

100990621 is a deficient number, since it is larger than the sum of its proper divisors (1).

100990621 is an equidigital number, since it uses as much as digits as its factorization.

100990621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 100990621 is about 10049.4089875972. The cubic root of 100990621 is about 465.6865351222.

The spelling of 100990621 in words is "one hundred million, nine hundred ninety thousand, six hundred twenty-one".