126856639728 has 320 divisors, whose sum is σ = 449554560000. Its totient is φ = 33352197120.

The previous prime is 126856639697. The next prime is 126856639783. The reversal of 126856639728 is 827936658621.

It is a happy number.

126856639728 is a `hidden beast` number, since 1 + 2 + 68 + 566 + 3 + 9 + 7 + 2 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13007398 + ... + 13017146.

It is an arithmetic number, because the mean of its divisors is an integer number (1404858000).

Almost surely, 2^126856639728 is an apocalyptic number.

126856639728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 126856639728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (224777280000).

126856639728 is an abundant number, since it is smaller than the sum of its proper divisors (322697920272).

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

126856639728 is a wasteful number, since it uses less digits than its factorization.

126856639728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10117 (or 10105 counting only the distinct ones).

The product of its digits is 52254720, while the sum is 63.

The spelling of 126856639728 in words is "one hundred twenty-six billion, eight hundred fifty-six million, six hundred thirty-nine thousand, seven hundred twenty-eight".