21087284325 has 12 divisors (see below), whose sum is σ = 34864310208. Its totient is φ = 11246551600.

The previous prime is 21087284321. The next prime is 21087284333. The reversal of 21087284325 is 52348278012.

It is not a de Polignac number, because 21087284325 - 2² = 21087284321 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21087284321) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 140581821 + ... + 140581970.

It is an arithmetic number, because the mean of its divisors is an integer number (2905359184).

Almost surely, 2^21087284325 is an apocalyptic number.

21087284325 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21087284325 is a deficient number, since it is larger than the sum of its proper divisors (13777025883).

21087284325 is a wasteful number, since it uses less digits than its factorization.

21087284325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281163804 (or 281163799 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 42.

The spelling of 21087284325 in words is "twenty-one billion, eighty-seven million, two hundred eighty-four thousand, three hundred twenty-five".