78398320784 has 40 divisors (see below), whose sum is σ = 174921476928. Its totient is φ = 33342791040.

The previous prime is 78398320783. The next prime is 78398320807. The reversal of 78398320784 is 48702389387.

It is a happy number.

It is a super-2 number, since 2×78398320784² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78398320783) 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, 2657027 + ... + 2686370.

Almost surely, 2^78398320784 is an apocalyptic number.

It is an amenable number.

78398320784 is an abundant number, since it is smaller than the sum of its proper divisors (96523156144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78398320784 is a wasteful number, since it uses less digits than its factorization.

78398320784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5343543 (or 5343537 counting only the distinct ones).

The product of its (nonzero) digits is 16257024, while the sum is 59.

The spelling of 78398320784 in words is "seventy-eight billion, three hundred ninety-eight million, three hundred twenty thousand, seven hundred eighty-four".