78987655 has 16 divisors (see below), whose sum is σ = 99993600. Its totient is φ = 59732640.

The previous prime is 78987653. The next prime is 78987673. The reversal of 78987655 is 55678987.

It is not a de Polignac number, because 78987655 - 2¹ = 78987653 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78987596 and 78987605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78987653) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 79210 + ... + 80200.

It is an arithmetic number, because the mean of its divisors is an integer number (6249600).

Almost surely, 2^78987655 is an apocalyptic number.

78987655 is a deficient number, since it is larger than the sum of its proper divisors (21005945).

78987655 is a wasteful number, since it uses less digits than its factorization.

78987655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1854.

The product of its digits is 4233600, while the sum is 55.

The square root of 78987655 is about 8887.4999296765. The cubic root of 78987655 is about 429.0616911480.

The spelling of 78987655 in words is "seventy-eight million, nine hundred eighty-seven thousand, six hundred fifty-five".