78971121415 has 4 divisors (see below), whose sum is σ = 94765345704. Its totient is φ = 63176897128.

The previous prime is 78971121407. The next prime is 78971121431. The reversal of 78971121415 is 51412117987.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78971121415 - 2³ = 78971121407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7897112137 + ... + 7897112146.

It is an arithmetic number, because the mean of its divisors is an integer number (23691336426).

Almost surely, 2^78971121415 is an apocalyptic number.

78971121415 is a deficient number, since it is larger than the sum of its proper divisors (15794224289).

78971121415 is a wasteful number, since it uses less digits than its factorization.

78971121415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15794224288.

The product of its digits is 141120, while the sum is 46.

The spelling of 78971121415 in words is "seventy-eight billion, nine hundred seventy-one million, one hundred twenty-one thousand, four hundred fifteen".