220990021 has 16 divisors (see below), whose sum is σ = 269080704. Its totient is φ = 177168384.

The previous prime is 220990009. The next prime is 220990037. The reversal of 220990021 is 120099022.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-220990021 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 (220990001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13701 + ... + 25093.

It is an arithmetic number, because the mean of its divisors is an integer number (16817544).

Almost surely, 2^220990021 is an apocalyptic number.

It is an amenable number.

220990021 is a deficient number, since it is larger than the sum of its proper divisors (48090683).

220990021 is a wasteful number, since it uses less digits than its factorization.

220990021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11580.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 220990021 is about 14865.7331134391. The cubic root of 220990021 is about 604.5852595440.

The spelling of 220990021 in words is "two hundred twenty million, nine hundred ninety thousand, twenty-one".