21685863195 has 12 divisors (see below), whose sum is σ = 37588829616. Its totient is φ = 11565793680.

The previous prime is 21685863181. The next prime is 21685863197. The reversal of 21685863195 is 59136858612.

21685863195 is a `hidden beast` number, since 21 + 6 + 8 + 586 + 31 + 9 + 5 = 666.

It is not a de Polignac number, because 21685863195 - 2¹⁶ = 21685797659 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21685863197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 240953991 + ... + 240954080.

It is an arithmetic number, because the mean of its divisors is an integer number (3132402468).

Almost surely, 2^21685863195 is an apocalyptic number.

21685863195 is a deficient number, since it is larger than the sum of its proper divisors (15902966421).

21685863195 is a wasteful number, since it uses less digits than its factorization.

21685863195 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481908082 (or 481908079 counting only the distinct ones).

The product of its digits is 3110400, while the sum is 54.

The spelling of 21685863195 in words is "twenty-one billion, six hundred eighty-five million, eight hundred sixty-three thousand, one hundred ninety-five".