77288861 has 8 divisors (see below), whose sum is σ = 83330520. Its totient is φ = 71260992.

The previous prime is 77288843. The next prime is 77288863. The reversal of 77288861 is 16888277.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 12180100 + 65108761 = 3490^2 + 8069^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77288861 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77288863) 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, 10235 + ... + 16103.

It is an arithmetic number, because the mean of its divisors is an integer number (10416315).

Almost surely, 2^77288861 is an apocalyptic number.

It is an amenable number.

77288861 is a deficient number, since it is larger than the sum of its proper divisors (6041659).

77288861 is a wasteful number, since it uses less digits than its factorization.

77288861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6895.

The product of its digits is 301056, while the sum is 47.

The square root of 77288861 is about 8791.4083627141. The cubic root of 77288861 is about 425.9634171823.

The spelling of 77288861 in words is "seventy-seven million, two hundred eighty-eight thousand, eight hundred sixty-one".