78977987 has 8 divisors (see below), whose sum is σ = 88937472. Its totient is φ = 69481800.

The previous prime is 78977957. The next prime is 78978007.

78977987 is nontrivially palindromic in base 10.

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-78977987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78977947) 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, 115463 + ... + 116144.

It is an arithmetic number, because the mean of its divisors is an integer number (11117184).

Almost surely, 2^78977987 is an apocalyptic number.

78977987 is a deficient number, since it is larger than the sum of its proper divisors (9959485).

78977987 is a wasteful number, since it uses less digits than its factorization.

78977987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231649.

The product of its digits is 12446784, while the sum is 62.

The square root of 78977987 is about 8886.9560030418. The cubic root of 78977987 is about 429.0441848778.

The spelling of 78977987 in words is "seventy-eight million, nine hundred seventy-seven thousand, nine hundred eighty-seven".