21353801048640 has 392 divisors, whose sum is σ = 76270776681408. Its totient is φ = 5691916293120.

The previous prime is 21353801048639. The next prime is 21353801048677. The reversal of 21353801048640 is 4684010835312.

21353801048640 is a `hidden beast` number, since 2 + 1 + 3 + 53 + 80 + 1 + 0 + 486 + 40 = 666.

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 55 ways as a sum of consecutive naturals, for example, 583881555 + ... + 583918125.

Almost surely, 2^{21353801048640} is an apocalyptic number.

21353801048640 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 21353801048640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38135388340704).

21353801048640 is an abundant number, since it is smaller than the sum of its proper divisors (54916975632768).

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

21353801048640 is an equidigital number, since it uses as much as digits as its factorization.

21353801048640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39109 (or 39084 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 45.

The spelling of 21353801048640 in words is "twenty-one trillion, three hundred fifty-three billion, eight hundred one million, forty-eight thousand, six hundred forty".