21358245888 has 288 divisors, whose sum is σ = 73121892480. Its totient is φ = 6101360640.

The previous prime is 21358245833. The next prime is 21358245917. The reversal of 21358245888 is 88854285312.

21358245888 is a `hidden beast` number, since 2 + 1 + 3 + 58 + 2 + 4 + 588 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

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, 3480583 + ... + 3486713.

It is an arithmetic number, because the mean of its divisors is an integer number (253895460).

Almost surely, 2^21358245888 is an apocalyptic number.

21358245888 is a gapful number since it is divisible by the number (28) 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 21358245888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36560946240).

21358245888 is an abundant number, since it is smaller than the sum of its proper divisors (51763646592).

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

21358245888 is an frugal number, since it uses more digits than its factorization.

21358245888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6175 (or 6143 counting only the distinct ones).

The product of its digits is 4915200, while the sum is 54.

The spelling of 21358245888 in words is "twenty-one billion, three hundred fifty-eight million, two hundred forty-five thousand, eight hundred eighty-eight".