78158963594 has 4 divisors (see below), whose sum is σ = 117238445394. Its totient is φ = 39079481796.

The previous prime is 78158963591. The next prime is 78158963599. The reversal of 78158963594 is 49536985187.

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

It can be written as a sum of positive squares in only one way, i.e., 66415990369 + 11742973225 = 257713^2 + 108365^2 .

It is a super-2 number, since 2×78158963594² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78158963594.

It is not an unprimeable number, because it can be changed into a prime (78158963591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19539740897 + ... + 19539740900.

Almost surely, 2^78158963594 is an apocalyptic number.

78158963594 is a deficient number, since it is larger than the sum of its proper divisors (39079481800).

78158963594 is a wasteful number, since it uses less digits than its factorization.

78158963594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39079481799.

The product of its digits is 65318400, while the sum is 65.

The spelling of 78158963594 in words is "seventy-eight billion, one hundred fifty-eight million, nine hundred sixty-three thousand, five hundred ninety-four".