81042577 has 16 divisors (see below), whose sum is σ = 102758400. Its totient is φ = 62076240.

The previous prime is 81042571. The next prime is 81042613. The reversal of 81042577 is 77524018.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 81042577 - 2⁷ = 81042449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81042571) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4377 + ... + 13462.

It is an arithmetic number, because the mean of its divisors is an integer number (6422400).

Almost surely, 2^81042577 is an apocalyptic number.

It is an amenable number.

81042577 is a deficient number, since it is larger than the sum of its proper divisors (21715823).

81042577 is a wasteful number, since it uses less digits than its factorization.

81042577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17916.

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 81042577 is about 9002.3650781336. The cubic root of 81042577 is about 432.7506685043.

The spelling of 81042577 in words is "eighty-one million, forty-two thousand, five hundred seventy-seven".