21254545152 has 216 divisors, whose sum is σ = 64640110080. Its totient is φ = 6963563520.

The previous prime is 21254545079. The next prime is 21254545189. The reversal of 21254545152 is 25154545212.

21254545152 is a `hidden beast` number, since 2 + 12 + 54 + 545 + 1 + 52 = 666.

It is a tau number, because it is divible by the number of its divisors (216).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3667377 + ... + 3673167.

Almost surely, 2^21254545152 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 21254545152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32320055040).

21254545152 is an abundant number, since it is smaller than the sum of its proper divisors (43385564928).

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

21254545152 is an frugal number, since it uses more digits than its factorization.

21254545152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5881 (or 5855 counting only the distinct ones).

The product of its digits is 80000, while the sum is 36.

The spelling of 21254545152 in words is "twenty-one billion, two hundred fifty-four million, five hundred forty-five thousand, one hundred fifty-two".