21344311220 has 24 divisors (see below), whose sum is σ = 44932662600. Its totient is φ = 8516846592.

The previous prime is 21344311217. The next prime is 21344311267. The reversal of 21344311220 is 2211344312.

It can be written as a sum of positive squares in 4 ways, for example, as 2215208356 + 19129102864 = 47066^2 + 138308^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1296485 + ... + 1312844.

It is an arithmetic number, because the mean of its divisors is an integer number (1872194275).

Almost surely, 2^21344311220 is an apocalyptic number.

21344311220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21344311220 is an abundant number, since it is smaller than the sum of its proper divisors (23588351380).

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

21344311220 is a wasteful number, since it uses less digits than its factorization.

21344311220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2609747 (or 2609745 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21344311220 its reverse (2211344312), we get a palindrome (23555655532).

The spelling of 21344311220 in words is "twenty-one billion, three hundred forty-four million, three hundred eleven thousand, two hundred twenty".