81495937 has 2 divisors, whose sum is σ = 81495938. Its totient is φ = 81495936.

The previous prime is 81495863. The next prime is 81495949. The reversal of 81495937 is 73959418.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70711281 + 10784656 = 8409^2 + 3284^2 .

It is a cyclic number.

It is not a de Polignac number, because 81495937 - 2⁷ = 81495809 is a prime.

It is not a weakly prime, because it can be changed into another prime (81495137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40747968 + 40747969.

It is an arithmetic number, because the mean of its divisors is an integer number (40747969).

Almost surely, 2^81495937 is an apocalyptic number.

It is an amenable number.

81495937 is a deficient number, since it is larger than the sum of its proper divisors (1).

81495937 is an equidigital number, since it uses as much as digits as its factorization.

81495937 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 272160, while the sum is 46.

The square root of 81495937 is about 9027.5100110717. The cubic root of 81495937 is about 433.5561181184.

The spelling of 81495937 in words is "eighty-one million, four hundred ninety-five thousand, nine hundred thirty-seven".