78720390965 has 16 divisors (see below), whose sum is σ = 95250931776. Its totient is φ = 62452665600.

The previous prime is 78720390923. The next prime is 78720390979. The reversal of 78720390965 is 56909302787.

It is not a de Polignac number, because 78720390965 - 2¹² = 78720386869 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78720390965.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 930845 + ... + 1011885.

It is an arithmetic number, because the mean of its divisors is an integer number (5953183236).

Almost surely, 2^78720390965 is an apocalyptic number.

It is an amenable number.

78720390965 is a deficient number, since it is larger than the sum of its proper divisors (16530540811).

78720390965 is a wasteful number, since it uses less digits than its factorization.

78720390965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82660.

The product of its (nonzero) digits is 5715360, while the sum is 56.

The spelling of 78720390965 in words is "seventy-eight billion, seven hundred twenty million, three hundred ninety thousand, nine hundred sixty-five".