21198789725085 has 24 divisors (see below), whose sum is σ = 41993792979840. Its totient is φ = 9690875302752.

The previous prime is 21198789725077. The next prime is 21198789725143. The reversal of 21198789725085 is 58052798789112.

21198789725085 is a `hidden beast` number, since 21 + 1 + 9 + 8 + 7 + 8 + 97 + 2 + 508 + 5 = 666.

It is not a de Polignac number, because 21198789725085 - 2³ = 21198789725077 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33648872265 + ... + 33648872894.

It is an arithmetic number, because the mean of its divisors is an integer number (1749741374160).

Almost surely, 2^{21198789725085} is an apocalyptic number.

It is an amenable number.

21198789725085 is a deficient number, since it is larger than the sum of its proper divisors (20795003254755).

21198789725085 is a wasteful number, since it uses less digits than its factorization.

21198789725085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67297745177 (or 67297745174 counting only the distinct ones).

The product of its (nonzero) digits is 203212800, while the sum is 72.

The spelling of 21198789725085 in words is "twenty-one trillion, one hundred ninety-eight billion, seven hundred eighty-nine million, seven hundred twenty-five thousand, eighty-five".