126921543840 has 1152 divisors, whose sum is σ = 572338690560. Its totient is φ = 25834733568.

The previous prime is 126921543829. The next prime is 126921543901. The reversal of 126921543840 is 48345129621.

126921543840 is a `hidden beast` number, since 1 + 2 + 6 + 9 + 21 + 543 + 84 + 0 = 666.

It is a super-2 number, since 2×126921543840² (a number of 23 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 102603702 + ... + 102604938.

It is an arithmetic number, because the mean of its divisors is an integer number (496821780).

Almost surely, 2^126921543840 is an apocalyptic number.

126921543840 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 126921543840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (286169345280).

126921543840 is an abundant number, since it is smaller than the sum of its proper divisors (445417146720).

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

126921543840 is a wasteful number, since it uses less digits than its factorization.

126921543840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1316 (or 1296 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

It can be divided in two parts, 126921 and 543840, that added together give a square (670761 = 819²).

The spelling of 126921543840 in words is "one hundred twenty-six billion, nine hundred twenty-one million, five hundred forty-three thousand, eight hundred forty".