21284097787925 has 24 divisors (see below), whose sum is σ = 30164959265472. Its totient is φ = 14593671792000.

The previous prime is 21284097787921. The next prime is 21284097788011. The reversal of 21284097787925 is 52978779048212.

It is not a de Polignac number, because 21284097787925 - 2² = 21284097787921 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 (21284097787921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2488571 + ... + 6982920.

It is an arithmetic number, because the mean of its divisors is an integer number (1256873302728).

Almost surely, 2^{21284097787925} is an apocalyptic number.

21284097787925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21284097787925 is a deficient number, since it is larger than the sum of its proper divisors (8880861477547).

21284097787925 is a wasteful number, since it uses less digits than its factorization.

21284097787925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9484349 (or 9484344 counting only the distinct ones).

The product of its (nonzero) digits is 284497920, while the sum is 71.

The spelling of 21284097787925 in words is "twenty-one trillion, two hundred eighty-four billion, ninety-seven million, seven hundred eighty-seven thousand, nine hundred twenty-five".