990121301002021 has 16 divisors (see below), whose sum is σ = 1053155386166400. Its totient is φ = 928201725085248.

The previous prime is 990121301001979. The next prime is 990121301002033. The reversal of 990121301002021 is 120200103121099.

It is a cyclic number.

It is not a de Polignac number, because 990121301002021 - 2¹¹ = 990121300999973 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 (990121301002051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 307641361 + ... + 310843126.

It is an arithmetic number, because the mean of its divisors is an integer number (65822211635400).

Almost surely, 2^{990121301002021} is an apocalyptic number.

It is an amenable number.

990121301002021 is a deficient number, since it is larger than the sum of its proper divisors (63034085164379).

990121301002021 is a wasteful number, since it uses less digits than its factorization.

990121301002021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618485388.

The product of its (nonzero) digits is 1944, while the sum is 31.

The spelling of 990121301002021 in words is "nine hundred ninety trillion, one hundred twenty-one billion, three hundred one million, two thousand, twenty-one".