78639271 has 24 divisors (see below), whose sum is σ = 89233200. Its totient is φ = 68987520.

The previous prime is 78639241. The next prime is 78639293. The reversal of 78639271 is 17293687.

It is a happy number.

It is not a de Polignac number, because 78639271 - 2¹³ = 78631079 is a prime.

It is a super-2 number, since 2×78639271² = 12368269886822882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78639221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1332840 + ... + 1332898.

It is an arithmetic number, because the mean of its divisors is an integer number (3718050).

Almost surely, 2^78639271 is an apocalyptic number.

78639271 is a deficient number, since it is larger than the sum of its proper divisors (10593929).

78639271 is a wasteful number, since it uses less digits than its factorization.

78639271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207 (or 148 counting only the distinct ones).

The product of its digits is 127008, while the sum is 43.

The square root of 78639271 is about 8867.8786076491. The cubic root of 78639271 is about 428.4299530540.

The spelling of 78639271 in words is "seventy-eight million, six hundred thirty-nine thousand, two hundred seventy-one".