21299611725 has 144 divisors (see below), whose sum is σ = 46608516864. Its totient is φ = 9085824000.

The previous prime is 21299611721. The next prime is 21299611757. The reversal of 21299611725 is 52711699212.

21299611725 is a `hidden beast` number, since 2 + 1 + 2 + 9 + 9 + 611 + 7 + 25 = 666.

It is not a de Polignac number, because 21299611725 - 2² = 21299611721 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21299611721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1478055 + ... + 1492395.

It is an arithmetic number, because the mean of its divisors is an integer number (323670256).

Almost surely, 2^21299611725 is an apocalyptic number.

21299611725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21299611725 is an abundant number, since it is smaller than the sum of its proper divisors (25308905139).

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

21299611725 is a wasteful number, since it uses less digits than its factorization.

21299611725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14428 (or 14420 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The spelling of 21299611725 in words is "twenty-one billion, two hundred ninety-nine million, six hundred eleven thousand, seven hundred twenty-five".