21021200090 has 16 divisors (see below), whose sum is σ = 41277993120. Its totient is φ = 7644072720.

The previous prime is 21021200089. The next prime is 21021200141. The reversal of 21021200090 is 9000212012.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95550800 + ... + 95551019.

It is an arithmetic number, because the mean of its divisors is an integer number (2579874570).

Almost surely, 2^21021200090 is an apocalyptic number.

21021200090 is a deficient number, since it is larger than the sum of its proper divisors (20256793030).

21021200090 is a wasteful number, since it uses less digits than its factorization.

21021200090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191101837.

The product of its (nonzero) digits is 72, while the sum is 17.

The spelling of 21021200090 in words is "twenty-one billion, twenty-one million, two hundred thousand, ninety".