78906885121 has 4 divisors (see below), whose sum is σ = 81452268544. Its totient is φ = 76361501700.

The previous prime is 78906885119. The next prime is 78906885133. The reversal of 78906885121 is 12158860987.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78906885121 - 2¹ = 78906885119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78906882121) 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, 1272691665 + ... + 1272691726.

It is an arithmetic number, because the mean of its divisors is an integer number (20363067136).

Almost surely, 2^78906885121 is an apocalyptic number.

It is an amenable number.

78906885121 is a deficient number, since it is larger than the sum of its proper divisors (2545383423).

78906885121 is a wasteful number, since it uses less digits than its factorization.

78906885121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2545383422.

The product of its (nonzero) digits is 1935360, while the sum is 55.

The spelling of 78906885121 in words is "seventy-eight billion, nine hundred six million, eight hundred eighty-five thousand, one hundred twenty-one".