78091487 has 6 divisors (see below), whose sum is σ = 79814928. Its totient is φ = 76370672.

The previous prime is 78091477. The next prime is 78091493. The reversal of 78091487 is 78419087.

It is not a de Polignac number, because 78091487 - 2⁸ = 78091231 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78091477) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 59939 + ... + 61227.

It is an arithmetic number, because the mean of its divisors is an integer number (13302488).

Almost surely, 2^78091487 is an apocalyptic number.

78091487 is a deficient number, since it is larger than the sum of its proper divisors (1723441).

78091487 is an frugal number, since it uses more digits than its factorization.

78091487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2625 (or 1336 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 44.

The square root of 78091487 is about 8836.9387799169. The cubic root of 78091487 is about 427.4328510745.

The spelling of 78091487 in words is "seventy-eight million, ninety-one thousand, four hundred eighty-seven".