21525979453440 has 1152 divisors, whose sum is σ = 87376952033280. Its totient is φ = 4428103680000.

The previous prime is 21525979453397. The next prime is 21525979453457. The reversal of 21525979453440 is 4435497952512.

It is a super-3 number, since 3×21525979453440³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2627999745 + ... + 2628007935.

It is an arithmetic number, because the mean of its divisors is an integer number (75848048640).

Almost surely, 2^{21525979453440} is an apocalyptic number.

21525979453440 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 21525979453440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43688476016640).

21525979453440 is an abundant number, since it is smaller than the sum of its proper divisors (65850972579840).

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

21525979453440 is a wasteful number, since it uses less digits than its factorization.

21525979453440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8351 (or 8320 counting only the distinct ones).

The product of its (nonzero) digits is 54432000, while the sum is 60.

The spelling of 21525979453440 in words is "twenty-one trillion, five hundred twenty-five billion, nine hundred seventy-nine million, four hundred fifty-three thousand, four hundred forty".