21444442525 has 24 divisors (see below), whose sum is σ = 29018151648. Its totient is φ = 15590760000.

The previous prime is 21444442507. The next prime is 21444442529. The reversal of 21444442525 is 52524444412.

It is not a de Polignac number, because 21444442525 - 2⁹ = 21444442013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21444442529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 940510 + ... + 963040.

It is an arithmetic number, because the mean of its divisors is an integer number (1209089652).

Almost surely, 2^21444442525 is an apocalyptic number.

21444442525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21444442525 is a deficient number, since it is larger than the sum of its proper divisors (7573709123).

21444442525 is a wasteful number, since it uses less digits than its factorization.

21444442525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26013 (or 26008 counting only the distinct ones).

The product of its digits is 204800, while the sum is 37.

Adding to 21444442525 its reverse (52524444412), we get a palindrome (73968886937).

The spelling of 21444442525 in words is "twenty-one billion, four hundred forty-four million, four hundred forty-two thousand, five hundred twenty-five".