86813210921 has 2 divisors, whose sum is σ = 86813210922. Its totient is φ = 86813210920.

The previous prime is 86813210893. The next prime is 86813210941. The reversal of 86813210921 is 12901231868.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48692600896 + 38120610025 = 220664^2 + 195245^2 .

It is a cyclic number.

It is not a de Polignac number, because 86813210921 - 2⁶ = 86813210857 is a prime.

It is not a weakly prime, because it can be changed into another prime (86813210941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43406605460 + 43406605461.

It is an arithmetic number, because the mean of its divisors is an integer number (43406605461).

Almost surely, 2^86813210921 is an apocalyptic number.

It is an amenable number.

86813210921 is a deficient number, since it is larger than the sum of its proper divisors (1).

86813210921 is an equidigital number, since it uses as much as digits as its factorization.

86813210921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41472, while the sum is 41.

The spelling of 86813210921 in words is "eighty-six billion, eight hundred thirteen million, two hundred ten thousand, nine hundred twenty-one".