21941688187 has 8 divisors (see below), whose sum is σ = 22434982416. Its totient is φ = 21453844992.

The previous prime is 21941688133. The next prime is 21941688191. The reversal of 21941688187 is 78188614912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21941688187 - 2³¹ = 19794204539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21941688127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1354618 + ... + 1370719.

It is an arithmetic number, because the mean of its divisors is an integer number (2804372802).

Almost surely, 2^21941688187 is an apocalyptic number.

21941688187 is a deficient number, since it is larger than the sum of its proper divisors (493294229).

21941688187 is an equidigital number, since it uses as much as digits as its factorization.

21941688187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2725517.

The product of its digits is 1548288, while the sum is 55.

The spelling of 21941688187 in words is "twenty-one billion, nine hundred forty-one million, six hundred eighty-eight thousand, one hundred eighty-seven".