78994378281 has 96 divisors (see below), whose sum is σ = 137935257600. Its totient is φ = 39810476160.

The previous prime is 78994378277. The next prime is 78994378313. The reversal of 78994378281 is 18287349987.

It is not a de Polignac number, because 78994378281 - 2² = 78994378277 is a prime.

It is a super-2 number, since 2×78994378281² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78994378081) 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 95 ways as a sum of consecutive naturals, for example, 4671600 + ... + 4688478.

It is an arithmetic number, because the mean of its divisors is an integer number (1436825600).

Almost surely, 2^78994378281 is an apocalyptic number.

It is an amenable number.

78994378281 is a deficient number, since it is larger than the sum of its proper divisors (58940879319).

78994378281 is a wasteful number, since it uses less digits than its factorization.

78994378281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17019 (or 17012 counting only the distinct ones).

The product of its digits is 48771072, while the sum is 66.

The spelling of 78994378281 in words is "seventy-eight billion, nine hundred ninety-four million, three hundred seventy-eight thousand, two hundred eighty-one".