21091235088 has 240 divisors, whose sum is σ = 70119762048. Its totient is φ = 5344204800.

The previous prime is 21091235029. The next prime is 21091235131. The reversal of 21091235088 is 88053219012.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1660570 + ... + 1673222.

Almost surely, 2^21091235088 is an apocalyptic number.

21091235088 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 21091235088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35059881024).

21091235088 is an abundant number, since it is smaller than the sum of its proper divisors (49028526960).

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

21091235088 is a wasteful number, since it uses less digits than its factorization.

21091235088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12734 (or 12717 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 39.

The spelling of 21091235088 in words is "twenty-one billion, ninety-one million, two hundred thirty-five thousand, eighty-eight".