21369432349440 has 864 divisors, whose sum is σ = 94177783365120. Its totient is φ = 4355162505216.

The previous prime is 21369432349381. The next prime is 21369432349477. The reversal of 21369432349440 is 4494323496312.

21369432349440 is a `hidden beast` number, since 2 + 1 + 3 + 6 + 94 + 3 + 23 + 494 + 40 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 25636507 + ... + 26456933.

It is an arithmetic number, because the mean of its divisors is an integer number (109002064080).

Almost surely, 2^{21369432349440} is an apocalyptic number.

21369432349440 is a gapful number since it is divisible by the number (20) 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 21369432349440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47088891682560).

21369432349440 is an abundant number, since it is smaller than the sum of its proper divisors (72808351015680).

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

21369432349440 is a wasteful number, since it uses less digits than its factorization.

21369432349440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820497 (or 820480 counting only the distinct ones).

The product of its (nonzero) digits is 13436928, while the sum is 54.

The spelling of 21369432349440 in words is "twenty-one trillion, three hundred sixty-nine billion, four hundred thirty-two million, three hundred forty-nine thousand, four hundred forty".