990102001021 has 4 divisors (see below), whose sum is σ = 1131545144032. Its totient is φ = 848658858012.

The previous prime is 990102000983. The next prime is 990102001067. The reversal of 990102001021 is 120100201099.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 990102001021 - 2¹³ = 990101992829 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 (990102001121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70721571495 + ... + 70721571508.

It is an arithmetic number, because the mean of its divisors is an integer number (282886286008).

Almost surely, 2^990102001021 is an apocalyptic number.

It is an amenable number.

990102001021 is a deficient number, since it is larger than the sum of its proper divisors (141443143011).

990102001021 is a wasteful number, since it uses less digits than its factorization.

990102001021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141443143010.

The product of its (nonzero) digits is 324, while the sum is 25.

The spelling of 990102001021 in words is "nine hundred ninety billion, one hundred two million, one thousand, twenty-one".