126981899840 has 112 divisors (see below), whose sum is σ = 324549253872. Its totient is φ = 47149940736.

The previous prime is 126981899839. The next prime is 126981899861. The reversal of 126981899840 is 48998189621.

It can be written as a sum of positive squares in 8 ways, for example, as 23658496 + 126958241344 = 4864^2 + 356312^2 .

It is a super-2 number, since 2×126981899840² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 237242 + ... + 556998.

Almost surely, 2^126981899840 is an apocalyptic number.

126981899840 is a gapful number since it is divisible by the number (10) 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 126981899840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162274626936).

126981899840 is an abundant number, since it is smaller than the sum of its proper divisors (197567354032).

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

126981899840 is a wasteful number, since it uses less digits than its factorization.

126981899840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319864 (or 319854 counting only the distinct ones).

The product of its (nonzero) digits is 17915904, while the sum is 65.

The spelling of 126981899840 in words is "one hundred twenty-six billion, nine hundred eighty-one million, eight hundred ninety-nine thousand, eight hundred forty".