78972671 has 4 divisors (see below), whose sum is σ = 78990600. Its totient is φ = 78954744.

The previous prime is 78972631. The next prime is 78972697. The reversal of 78972671 is 17627987.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17627987 = 13 ⋅1355999.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78972671 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 (78972631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2720 + ... + 12858.

It is an arithmetic number, because the mean of its divisors is an integer number (19747650).

Almost surely, 2^78972671 is an apocalyptic number.

78972671 is a deficient number, since it is larger than the sum of its proper divisors (17929).

78972671 is a wasteful number, since it uses less digits than its factorization.

78972671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17928.

The product of its digits is 296352, while the sum is 47.

The square root of 78972671 is about 8886.6569079716. The cubic root of 78972671 is about 429.0345583555.

The spelling of 78972671 in words is "seventy-eight million, nine hundred seventy-two thousand, six hundred seventy-one".