78978373501 has 4 divisors (see below), whose sum is σ = 78980133052. Its totient is φ = 78976613952.

The previous prime is 78978373399. The next prime is 78978373517. The reversal of 78978373501 is 10537387987.

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

It can be written as a sum of positive squares in 2 ways, for example, as 43662192025 + 35316181476 = 208955^2 + 187926^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78978373501 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 (78978373531) 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, 810636 + ... + 902821.

It is an arithmetic number, because the mean of its divisors is an integer number (19745033263).

Almost surely, 2^78978373501 is an apocalyptic number.

It is an amenable number.

78978373501 is a deficient number, since it is larger than the sum of its proper divisors (1759551).

78978373501 is a wasteful number, since it uses less digits than its factorization.

78978373501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1759550.

The product of its (nonzero) digits is 8890560, while the sum is 58.

The spelling of 78978373501 in words is "seventy-eight billion, nine hundred seventy-eight million, three hundred seventy-three thousand, five hundred one".