78239436394 has 48 divisors (see below), whose sum is σ = 139840549632. Its totient is φ = 32137044192.

The previous prime is 78239436389. The next prime is 78239436511. The reversal of 78239436394 is 49363493287.

It is a super-2 number, since 2×78239436394² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2308479 + ... + 2342125.

It is an arithmetic number, because the mean of its divisors is an integer number (2913344784).

Almost surely, 2^78239436394 is an apocalyptic number.

78239436394 is a gapful number since it is divisible by the number (74) formed by its first and last digit.

78239436394 is a deficient number, since it is larger than the sum of its proper divisors (61601113238).

78239436394 is a wasteful number, since it uses less digits than its factorization.

78239436394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33827 (or 33760 counting only the distinct ones).

The product of its digits is 23514624, while the sum is 58.

The spelling of 78239436394 in words is "seventy-eight billion, two hundred thirty-nine million, four hundred thirty-six thousand, three hundred ninety-four".