78672577637 has 4 divisors (see below), whose sum is σ = 80591421036. Its totient is φ = 76753734240.

The previous prime is 78672577631. The next prime is 78672577693. The reversal of 78672577637 is 73677527687.

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 11901500836 + 66771076801 = 109094^2 + 258401^2 .

It is a cyclic number.

It is not a de Polignac number, because 78672577637 - 2³² = 74377610341 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 (78672577631) 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, 959421638 + ... + 959421719.

It is an arithmetic number, because the mean of its divisors is an integer number (20147855259).

Almost surely, 2^78672577637 is an apocalyptic number.

It is an amenable number.

78672577637 is a deficient number, since it is larger than the sum of its proper divisors (1918843399).

78672577637 is a wasteful number, since it uses less digits than its factorization.

78672577637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1918843398.

The product of its digits is 145212480, while the sum is 65.

The spelling of 78672577637 in words is "seventy-eight billion, six hundred seventy-two million, five hundred seventy-seven thousand, six hundred thirty-seven".