77665577 has 8 divisors (see below), whose sum is σ = 85374432. Its totient is φ = 70064800.

The previous prime is 77665561. The next prime is 77665589. The reversal of 77665577 is 77556677.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77665577 - 2⁴ = 77665561 is a prime.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (77665547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25508 + ... + 28389.

It is an arithmetic number, because the mean of its divisors is an integer number (10671804).

Almost surely, 2^77665577 is an apocalyptic number.

It is an amenable number.

77665577 is a deficient number, since it is larger than the sum of its proper divisors (7708855).

77665577 is a wasteful number, since it uses less digits than its factorization.

77665577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54039.

The product of its digits is 2160900, while the sum is 50.

The square root of 77665577 is about 8812.8075549169. The cubic root of 77665577 is about 426.6543629129.

Subtracting from 77665577 its reverse (77556677), we obtain a square (108900 = 330²).

The spelling of 77665577 in words is "seventy-seven million, six hundred sixty-five thousand, five hundred seventy-seven".