81374497 has 4 divisors (see below), whose sum is σ = 81477396. Its totient is φ = 81271600.

The previous prime is 81374477. The next prime is 81374519. The reversal of 81374497 is 79447318.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18584721 + 62789776 = 4311^2 + 7924^2 .

It is a cyclic number.

It is not a de Polignac number, because 81374497 - 2⁷ = 81374369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81374407) 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 in 3 ways as a sum of consecutive naturals, for example, 50254 + ... + 51847.

It is an arithmetic number, because the mean of its divisors is an integer number (20369349).

Almost surely, 2^81374497 is an apocalyptic number.

It is an amenable number.

81374497 is a deficient number, since it is larger than the sum of its proper divisors (102899).

81374497 is a wasteful number, since it uses less digits than its factorization.

81374497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102898.

The product of its digits is 169344, while the sum is 43.

The square root of 81374497 is about 9020.7813963093. The cubic root of 81374497 is about 433.3406585875.

The spelling of 81374497 in words is "eighty-one million, three hundred seventy-four thousand, four hundred ninety-seven".