78977985 has 16 divisors (see below), whose sum is σ = 126478464. Its totient is φ = 42083712.

The previous prime is 78977957. The next prime is 78978007. The reversal of 78977985 is 58977987.

It is not a de Polignac number, because 78977985 - 2⁵ = 78977953 is a prime.

It is a super-2 number, since 2×78977985² = 12475044229320450, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25269 + ... + 28221.

It is an arithmetic number, because the mean of its divisors is an integer number (7904904).

Almost surely, 2^78977985 is an apocalyptic number.

It is an amenable number.

78977985 is a deficient number, since it is larger than the sum of its proper divisors (47500479).

78977985 is a wasteful number, since it uses less digits than its factorization.

78977985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4744.

The product of its digits is 8890560, while the sum is 60.

The square root of 78977985 is about 8886.9558905173. The cubic root of 78977985 is about 429.0441812562.

The spelling of 78977985 in words is "seventy-eight million, nine hundred seventy-seven thousand, nine hundred eighty-five".