77286561 has 16 divisors (see below), whose sum is σ = 114540480. Its totient is φ = 45955520.

The previous prime is 77286551. The next prime is 77286581. The reversal of 77286561 is 16568277.

It is a cyclic number.

It is not a de Polignac number, because 77286561 - 2⁶ = 77286497 is a prime.

It is a super-2 number, since 2×77286561² = 11946425022413442, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77286511) 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, 20346 + ... + 23843.

It is an arithmetic number, because the mean of its divisors is an integer number (7158780).

Almost surely, 2^77286561 is an apocalyptic number.

It is an amenable number.

77286561 is a deficient number, since it is larger than the sum of its proper divisors (37253919).

77286561 is a wasteful number, since it uses less digits than its factorization.

77286561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44256.

The product of its digits is 141120, while the sum is 42.

The square root of 77286561 is about 8791.2775522105. The cubic root of 77286561 is about 425.9591917973.

The spelling of 77286561 in words is "seventy-seven million, two hundred eighty-six thousand, five hundred sixty-one".