86631212992921 has 3 divisors (see below), whose sum is σ = 86631222300511. Its totient is φ = 86631203685332.

The previous prime is 86631212992897. The next prime is 86631212992931. The reversal of 86631212992921 is 12929921213668.

The square root of 86631212992921 is 9307589.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 38224406742921 + 48406806250000 = 6182589^2 + 6957500^2 .

It is not a de Polignac number, because 86631212992921 - 2³³ = 86622623058329 is a prime.

It is a super-3 number, since 3×86631212992921³ (a number of 43 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 86631212992921.

It is not an unprimeable number, because it can be changed into a prime (86631212992931) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 4653795 + ... + 13961383.

Almost surely, 2^{86631212992921} is an apocalyptic number.

86631212992921 is the 9307589-th square number.

86631212992921 is the 4653795-th centered octagonal number.

It is an amenable number.

86631212992921 is a deficient number, since it is larger than the sum of its proper divisors (9307590).

86631212992921 is an frugal number, since it uses more digits than its factorization.

86631212992921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18615178 (or 9307589 counting only the distinct ones).

The product of its digits is 10077696, while the sum is 61.

The spelling of 86631212992921 in words is "eighty-six trillion, six hundred thirty-one billion, two hundred twelve million, nine hundred ninety-two thousand, nine hundred twenty-one".