21794748840 has 256 divisors, whose sum is σ = 74644416000. Its totient is φ = 5653186560.

The previous prime is 21794748823. The next prime is 21794748889. The reversal of 21794748840 is 4884749712.

21794748840 is a `hidden beast` number, since 21 + 79 + 474 + 8 + 84 + 0 = 666.

It is a super-2 number, since 2×21794748840² (a number of 21 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 22538037 + ... + 22539003.

It is an arithmetic number, because the mean of its divisors is an integer number (291579750).

Almost surely, 2^21794748840 is an apocalyptic number.

21794748840 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 21794748840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37322208000).

21794748840 is an abundant number, since it is smaller than the sum of its proper divisors (52849667160).

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

21794748840 is a wasteful number, since it uses less digits than its factorization.

21794748840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1537 (or 1527 counting only the distinct ones).

The product of its (nonzero) digits is 3612672, while the sum is 54.

The spelling of 21794748840 in words is "twenty-one billion, seven hundred ninety-four million, seven hundred forty-eight thousand, eight hundred forty".