78423933621 has 16 divisors (see below), whose sum is σ = 114181867008. Its totient is φ = 47483535600.

The previous prime is 78423933611. The next prime is 78423933647. The reversal of 78423933621 is 12633932487.

It is not a de Polignac number, because 78423933621 - 2⁹ = 78423933109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78423933611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1118491 + ... + 1186536.

It is an arithmetic number, because the mean of its divisors is an integer number (7136366688).

Almost surely, 2^78423933621 is an apocalyptic number.

It is an amenable number.

78423933621 is a deficient number, since it is larger than the sum of its proper divisors (35757933387).

78423933621 is a wasteful number, since it uses less digits than its factorization.

78423933621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2306072.

The product of its digits is 1306368, while the sum is 48.

The spelling of 78423933621 in words is "seventy-eight billion, four hundred twenty-three million, nine hundred thirty-three thousand, six hundred twenty-one".