21724218411960 has 128 divisors (see below), whose sum is σ = 65580451200000. Its totient is φ = 5756984134656.

The previous prime is 21724218411953. The next prime is 21724218411971. The reversal of 21724218411960 is 6911481242712.

It is a super-2 number, since 2×21724218411960² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

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, 12066541 + ... + 13749539.

It is an arithmetic number, because the mean of its divisors is an integer number (512347275000).

Almost surely, 2^{21724218411960} is an apocalyptic number.

21724218411960 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 21724218411960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32790225600000).

21724218411960 is an abundant number, since it is smaller than the sum of its proper divisors (43856232788040).

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

21724218411960 is a wasteful number, since it uses less digits than its factorization.

21724218411960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1683685 (or 1683681 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 48.

The spelling of 21724218411960 in words is "twenty-one trillion, seven hundred twenty-four billion, two hundred eighteen million, four hundred eleven thousand, nine hundred sixty".