21440440125 has 128 divisors (see below), whose sum is σ = 43395555840. Its totient is φ = 10380960000.

The previous prime is 21440440117. The next prime is 21440440187. The reversal of 21440440125 is 52104404412.

21440440125 is a `hidden beast` number, since 214 + 4 + 0 + 440 + 1 + 2 + 5 = 666.

It is not a de Polignac number, because 21440440125 - 2³ = 21440440117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2672370 + ... + 2680380.

It is an arithmetic number, because the mean of its divisors is an integer number (339027780).

Almost surely, 2^21440440125 is an apocalyptic number.

21440440125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21440440125 is an abundant number, since it is smaller than the sum of its proper divisors (21955115715).

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

21440440125 is a wasteful number, since it uses less digits than its factorization.

21440440125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8109 (or 8093 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 27.

Adding to 21440440125 its reverse (52104404412), we get a palindrome (73544844537).

The spelling of 21440440125 in words is "twenty-one billion, four hundred forty million, four hundred forty thousand, one hundred twenty-five".