77846721 has 8 divisors (see below), whose sum is σ = 104130624. Its totient is φ = 51730320.

The previous prime is 77846707. The next prime is 77846731. The reversal of 77846721 is 12764877.

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

It is not a de Polignac number, because 77846721 - 2²⁵ = 44292289 is a prime.

It is a super-2 number, since 2×77846721² = 12120223940903682, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77846731) 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, 40786 + ... + 42651.

It is an arithmetic number, because the mean of its divisors is an integer number (13016328).

Almost surely, 2^77846721 is an apocalyptic number.

It is an amenable number.

77846721 is a deficient number, since it is larger than the sum of its proper divisors (26283903).

77846721 is a wasteful number, since it uses less digits than its factorization.

77846721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83751.

The product of its digits is 131712, while the sum is 42.

The square root of 77846721 is about 8823.0788843804. The cubic root of 77846721 is about 426.9858090632.

The spelling of 77846721 in words is "seventy-seven million, eight hundred forty-six thousand, seven hundred twenty-one".