78980977 has 4 divisors (see below), whose sum is σ = 81115636. Its totient is φ = 76846320.

The previous prime is 78980939. The next prime is 78981029. The reversal of 78980977 is 77908987.

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

It can be written as a sum of positive squares in 2 ways, for example, as 76667536 + 2313441 = 8756^2 + 1521^2 .

It is a cyclic number.

It is not a de Polignac number, because 78980977 - 2⁷ = 78980849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78980477) 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, 1067274 + ... + 1067347.

It is an arithmetic number, because the mean of its divisors is an integer number (20278909).

Almost surely, 2^78980977 is an apocalyptic number.

It is an amenable number.

78980977 is a deficient number, since it is larger than the sum of its proper divisors (2134659).

78980977 is a wasteful number, since it uses less digits than its factorization.

78980977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2134658.

The product of its (nonzero) digits is 1778112, while the sum is 55.

The square root of 78980977 is about 8887.1242255299. The cubic root of 78980977 is about 429.0495991541.

The spelling of 78980977 in words is "seventy-eight million, nine hundred eighty thousand, nine hundred seventy-seven".