77554661 has 4 divisors (see below), whose sum is σ = 77577324. Its totient is φ = 77532000.

The previous prime is 77554651. The next prime is 77554667. The reversal of 77554661 is 16645577.

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 4024036 + 73530625 = 2006^2 + 8575^2 .

It is a cyclic number.

It is not a de Polignac number, because 77554661 - 2¹⁴ = 77538277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77554667) 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, 5030 + ... + 13431.

It is an arithmetic number, because the mean of its divisors is an integer number (19394331).

Almost surely, 2^77554661 is an apocalyptic number.

It is an amenable number.

77554661 is a deficient number, since it is larger than the sum of its proper divisors (22663).

77554661 is a wasteful number, since it uses less digits than its factorization.

77554661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22662.

The product of its digits is 176400, while the sum is 41.

The square root of 77554661 is about 8806.5124197948. The cubic root of 77554661 is about 426.4511611744.

The spelling of 77554661 in words is "seventy-seven million, five hundred fifty-four thousand, six hundred sixty-one".