21344312220 has 96 divisors (see below), whose sum is σ = 74511069696. Its totient is φ = 4435180800.

The previous prime is 21344312203. The next prime is 21344312233. The reversal of 21344312220 is 2221344312.

It is a happy number.

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, 2305371 + ... + 2314610.

It is an arithmetic number, because the mean of its divisors is an integer number (776156976).

Almost surely, 2^21344312220 is an apocalyptic number.

21344312220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21344312220 is an abundant number, since it is smaller than the sum of its proper divisors (53166757476).

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

21344312220 is a wasteful number, since it uses less digits than its factorization.

21344312220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4620011 (or 4620009 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21344312220 its reverse (2221344312), we get a palindrome (23565656532).

The spelling of 21344312220 in words is "twenty-one billion, three hundred forty-four million, three hundred twelve thousand, two hundred twenty".