86815973 has 2 divisors, whose sum is σ = 86815974. Its totient is φ = 86815972.

The previous prime is 86815969. The next prime is 86816017. The reversal of 86815973 is 37951868.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47100769 + 39715204 = 6863^2 + 6302^2 .

It is a cyclic number.

It is not a de Polignac number, because 86815973 - 2² = 86815969 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (86815913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43407986 + 43407987.

It is an arithmetic number, because the mean of its divisors is an integer number (43407987).

Almost surely, 2^86815973 is an apocalyptic number.

It is an amenable number.

86815973 is a deficient number, since it is larger than the sum of its proper divisors (1).

86815973 is an equidigital number, since it uses as much as digits as its factorization.

86815973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 47.

The square root of 86815973 is about 9317.5089482114. The cubic root of 86815973 is about 442.7921154162.

The spelling of 86815973 in words is "eighty-six million, eight hundred fifteen thousand, nine hundred seventy-three".