21050542240 has 192 divisors, whose sum is σ = 61986677760. Its totient is φ = 6577459200.

The previous prime is 21050542211. The next prime is 21050542267. The reversal of 21050542240 is 4224505012.

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, 1141090 + ... + 1159390.

It is an arithmetic number, because the mean of its divisors is an integer number (322847280).

Almost surely, 2^21050542240 is an apocalyptic number.

21050542240 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 21050542240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30993338880).

21050542240 is an abundant number, since it is smaller than the sum of its proper divisors (40936135520).

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

21050542240 is a wasteful number, since it uses less digits than its factorization.

21050542240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18415 (or 18407 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 25.

The spelling of 21050542240 in words is "twenty-one billion, fifty million, five hundred forty-two thousand, two hundred forty".