21069750240 has 768 divisors, whose sum is σ = 93030819840. Its totient is φ = 4326359040.

The previous prime is 21069750239. The next prime is 21069750281. The reversal of 21069750240 is 4205796012.

21069750240 is a `hidden beast` number, since 2 + 106 + 9 + 7 + 502 + 40 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 21069750195 and 21069750204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 32265754 + ... + 32266406.

It is an arithmetic number, because the mean of its divisors is an integer number (121133880).

Almost surely, 2^21069750240 is an apocalyptic number.

21069750240 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 21069750240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46515409920).

21069750240 is an abundant number, since it is smaller than the sum of its proper divisors (71961069600).

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

21069750240 is a wasteful number, since it uses less digits than its factorization.

21069750240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 792 (or 778 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The spelling of 21069750240 in words is "twenty-one billion, sixty-nine million, seven hundred fifty thousand, two hundred forty".