74164763581 has 4 divisors (see below), whose sum is σ = 74165343964. Its totient is φ = 74164183200.

The previous prime is 74164763521. The next prime is 74164763591. The reversal of 74164763581 is 18536746147.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 29025936900 + 45138826681 = 170370^2 + 212459^2 .

It is a cyclic number.

It is not a de Polignac number, because 74164763581 - 2⁹ = 74164763069 is a prime.

It is a super-2 number, since 2×74164763581² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74164763501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5250 + ... + 385171.

It is an arithmetic number, because the mean of its divisors is an integer number (18541335991).

Almost surely, 2^74164763581 is an apocalyptic number.

It is an amenable number.

74164763581 is a deficient number, since it is larger than the sum of its proper divisors (580383).

74164763581 is a wasteful number, since it uses less digits than its factorization.

74164763581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580382.

The product of its digits is 3386880, while the sum is 52.

The spelling of 74164763581 in words is "seventy-four billion, one hundred sixty-four million, seven hundred sixty-three thousand, five hundred eighty-one".