78638762757 has 4 divisors (see below), whose sum is σ = 104851683680. Its totient is φ = 52425841836.

The previous prime is 78638762753. The next prime is 78638762767. The reversal of 78638762757 is 75726783687.

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 not a de Polignac number, because 78638762757 - 2² = 78638762753 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 (78638762753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13106460457 + ... + 13106460462.

It is an arithmetic number, because the mean of its divisors is an integer number (26212920920).

Almost surely, 2^78638762757 is an apocalyptic number.

It is an amenable number.

78638762757 is a deficient number, since it is larger than the sum of its proper divisors (26212920923).

78638762757 is a wasteful number, since it uses less digits than its factorization.

78638762757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26212920922.

The product of its digits is 165957120, while the sum is 66.

The spelling of 78638762757 in words is "seventy-eight billion, six hundred thirty-eight million, seven hundred sixty-two thousand, seven hundred fifty-seven".