21554315206752 has 192 divisors, whose sum is σ = 59521454899200. Its totient is φ = 6816387561984.

The previous prime is 21554315206747. The next prime is 21554315206757. The reversal of 21554315206752 is 25760251345512.

It is an interprime number because it is at equal distance from previous prime (21554315206747) and next prime (21554315206757).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21554315206757) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1290746499 + ... + 1290763197.

It is an arithmetic number, because the mean of its divisors is an integer number (310007577600).

Almost surely, 2^{21554315206752} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21554315206752, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29760727449600).

21554315206752 is an abundant number, since it is smaller than the sum of its proper divisors (37967139692448).

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

21554315206752 is a wasteful number, since it uses less digits than its factorization.

21554315206752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21465 (or 21457 counting only the distinct ones).

The product of its (nonzero) digits is 2520000, while the sum is 48.

The spelling of 21554315206752 in words is "twenty-one trillion, five hundred fifty-four billion, three hundred fifteen million, two hundred six thousand, seven hundred fifty-two".