12721722523440 has 320 divisors, whose sum is σ = 45193070886912. Its totient is φ = 2899970841600.

The previous prime is 12721722523423. The next prime is 12721722523451. The reversal of 12721722523440 is 4432522712721.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 12721722523392 and 12721722523401.

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, 1510351069 + ... + 1510359491.

Almost surely, 2^{12721722523440} is an apocalyptic number.

12721722523440 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 12721722523440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22596535443456).

12721722523440 is an abundant number, since it is smaller than the sum of its proper divisors (32471348363472).

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

12721722523440 is a wasteful number, since it uses less digits than its factorization.

12721722523440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10768 (or 10762 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 42.

The spelling of 12721722523440 in words is "twelve trillion, seven hundred twenty-one billion, seven hundred twenty-two million, five hundred twenty-three thousand, four hundred forty".