21444014420 has 24 divisors (see below), whose sum is σ = 45770669448. Its totient is φ = 8436988800.

The previous prime is 21444014399. The next prime is 21444014497. The reversal of 21444014420 is 2441044412.

It can be written as a sum of positive squares in 4 ways, for example, as 1412707396 + 20031307024 = 37586^2 + 141532^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21444014420.

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, 8787311 + ... + 8789750.

It is an arithmetic number, because the mean of its divisors is an integer number (1907111227).

Almost surely, 2^21444014420 is an apocalyptic number.

21444014420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21444014420 is an abundant number, since it is smaller than the sum of its proper divisors (24326655028).

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

21444014420 is a wasteful number, since it uses less digits than its factorization.

21444014420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17577131 (or 17577129 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 26.

Adding to 21444014420 its reverse (2441044412), we get a palindrome (23885058832).

The spelling of 21444014420 in words is "twenty-one billion, four hundred forty-four million, fourteen thousand, four hundred twenty".