12921571440 has 320 divisors, whose sum is σ = 45528336000. Its totient is φ = 3367526400.

The previous prime is 12921571409. The next prime is 12921571489. The reversal of 12921571440 is 4417512921.

12921571440 is a `hidden beast` number, since 1 + 29 + 21 + 571 + 4 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 12921571395 and 12921571404.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 37024386 + ... + 37024734.

It is an arithmetic number, because the mean of its divisors is an integer number (142276050).

Almost surely, 2^12921571440 is an apocalyptic number.

12921571440 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 12921571440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22764168000).

12921571440 is an abundant number, since it is smaller than the sum of its proper divisors (32606764560).

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

12921571440 is a wasteful number, since it uses less digits than its factorization.

12921571440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 713 (or 701 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The spelling of 12921571440 in words is "twelve billion, nine hundred twenty-one million, five hundred seventy-one thousand, four hundred forty".