78189749386 has 16 divisors (see below), whose sum is σ = 135095003136. Its totient is φ = 33246034416.

The previous prime is 78189749381. The next prime is 78189749413. The reversal of 78189749386 is 68394798187.

It is a super-2 number, since 2×78189749386² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78189749381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21986341 + ... + 21989896.

It is an arithmetic number, because the mean of its divisors is an integer number (8443437696).

Almost surely, 2^78189749386 is an apocalyptic number.

78189749386 is a deficient number, since it is larger than the sum of its proper divisors (56905253750).

78189749386 is a wasteful number, since it uses less digits than its factorization.

78189749386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43976373.

The product of its digits is 146313216, while the sum is 70.

The spelling of 78189749386 in words is "seventy-eight billion, one hundred eighty-nine million, seven hundred forty-nine thousand, three hundred eighty-six".