21235762240 has 224 divisors, whose sum is σ = 64752102144. Its totient is φ = 6439772160.

The previous prime is 21235762217. The next prime is 21235762271. The reversal of 21235762240 is 4226753212.

It is a tau number, because it is divible by the number of its divisors (224).

It is a junction number, because it is equal to n+sod(n) for n = 21235762196 and 21235762205.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 900034 + ... + 923326.

Almost surely, 2^21235762240 is an apocalyptic number.

21235762240 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 21235762240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32376051072).

21235762240 is an abundant number, since it is smaller than the sum of its proper divisors (43516339904).

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

21235762240 is a wasteful number, since it uses less digits than its factorization.

21235762240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23365 (or 23355 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 34.

The spelling of 21235762240 in words is "twenty-one billion, two hundred thirty-five million, seven hundred sixty-two thousand, two hundred forty".