87990211221 has 16 divisors (see below), whose sum is σ = 127997029440. Its totient is φ = 53322705920.

The previous prime is 87990211213. The next prime is 87990211247. The reversal of 87990211221 is 12211209978.

It is not a de Polignac number, because 87990211221 - 2³ = 87990211213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87990211721) 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, 283591 + ... + 506363.

It is an arithmetic number, because the mean of its divisors is an integer number (7999814340).

Almost surely, 2^87990211221 is an apocalyptic number.

It is an amenable number.

87990211221 is a deficient number, since it is larger than the sum of its proper divisors (40006818219).

87990211221 is a wasteful number, since it uses less digits than its factorization.

87990211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234756.

The product of its (nonzero) digits is 36288, while the sum is 42.

The spelling of 87990211221 in words is "eighty-seven billion, nine hundred ninety million, two hundred eleven thousand, two hundred twenty-one".