12400939278 has 96 divisors (see below), whose sum is σ = 33159462336. Its totient is φ = 3261648384.

The previous prime is 12400939259. The next prime is 12400939283. The reversal of 12400939278 is 87293900421.

12400939278 is a `hidden beast` number, since 1 + 2 + 400 + 93 + 92 + 78 = 666.

It is a super-2 number, since 2×12400939278² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 600826 + ... + 621122.

It is an arithmetic number, because the mean of its divisors is an integer number (345411066).

Almost surely, 2^12400939278 is an apocalyptic number.

12400939278 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 12400939278, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16579731168).

12400939278 is an abundant number, since it is smaller than the sum of its proper divisors (20758523058).

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

12400939278 is a wasteful number, since it uses less digits than its factorization.

12400939278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20698 (or 20695 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 12400939278 in words is "twelve billion, four hundred million, nine hundred thirty-nine thousand, two hundred seventy-eight".