21245849809712 has 80 divisors (see below), whose sum is σ = 45400379046912. Its totient is φ = 9551184034560.

The previous prime is 21245849809687. The next prime is 21245849809747. The reversal of 21245849809712 is 21790894854212.

It is a super-2 number, since 2×21245849809712² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10501718 + ... + 12360330.

Almost surely, 2^{21245849809712} is an apocalyptic number.

21245849809712 is a gapful number since it is divisible by the number (22) 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 21245849809712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22700189523456).

21245849809712 is an abundant number, since it is smaller than the sum of its proper divisors (24154529237200).

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

21245849809712 is a wasteful number, since it uses less digits than its factorization.

21245849809712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1859346 (or 1859340 counting only the distinct ones).

The product of its (nonzero) digits is 23224320, while the sum is 62.

The spelling of 21245849809712 in words is "twenty-one trillion, two hundred forty-five billion, eight hundred forty-nine million, eight hundred nine thousand, seven hundred twelve".