77972847 has 4 divisors (see below), whose sum is σ = 103963800. Its totient is φ = 51981896.

The previous prime is 77972837. The next prime is 77972879. The reversal of 77972847 is 74827977.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 77972847 - 2⁴ = 77972831 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77972847.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77972837) 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, 12995472 + ... + 12995477.

It is an arithmetic number, because the mean of its divisors is an integer number (25990950).

Almost surely, 2^77972847 is an apocalyptic number.

77972847 is a deficient number, since it is larger than the sum of its proper divisors (25990953).

77972847 is a wasteful number, since it uses less digits than its factorization.

77972847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25990952.

The product of its digits is 1382976, while the sum is 51.

The square root of 77972847 is about 8830.2234966053. The cubic root of 77972847 is about 427.2162831416.

The spelling of 77972847 in words is "seventy-seven million, nine hundred seventy-two thousand, eight hundred forty-seven".