86518921 has 2 divisors, whose sum is σ = 86518922. Its totient is φ = 86518920.

The previous prime is 86518907. The next prime is 86518931. The reversal of 86518921 is 12981568.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85821696 + 697225 = 9264^2 + 835^2 .

It is a cyclic number.

It is not a de Polignac number, because 86518921 - 2⁹ = 86518409 is a prime.

It is not a weakly prime, because it can be changed into another prime (86518931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43259460 + 43259461.

It is an arithmetic number, because the mean of its divisors is an integer number (43259461).

Almost surely, 2^86518921 is an apocalyptic number.

It is an amenable number.

86518921 is a deficient number, since it is larger than the sum of its proper divisors (1).

86518921 is an equidigital number, since it uses as much as digits as its factorization.

86518921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 40.

The square root of 86518921 is about 9301.5547625115. The cubic root of 86518921 is about 442.2865149568.

The spelling of 86518921 in words is "eighty-six million, five hundred eighteen thousand, nine hundred twenty-one".