77661157 has 8 divisors (see below), whose sum is σ = 89111232. Its totient is φ = 66300000.

The previous prime is 77661137. The next prime is 77661161. The reversal of 77661157 is 75116677.

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 77661157 - 2¹⁹ = 77136869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77661137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20344 + ... + 23857.

It is an arithmetic number, because the mean of its divisors is an integer number (11138904).

Almost surely, 2^77661157 is an apocalyptic number.

It is an amenable number.

77661157 is a deficient number, since it is larger than the sum of its proper divisors (11450075).

77661157 is a wasteful number, since it uses less digits than its factorization.

77661157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44459.

The product of its digits is 61740, while the sum is 40.

The square root of 77661157 is about 8812.5567799589. The cubic root of 77661157 is about 426.6462690308.

The spelling of 77661157 in words is "seventy-seven million, six hundred sixty-one thousand, one hundred fifty-seven".