21106188971 has 8 divisors (see below), whose sum is σ = 24426693120. Its totient is φ = 17862018408.

The previous prime is 21106188953. The next prime is 21106188973. The reversal of 21106188971 is 17988160112.

It is a happy number.

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 21106188971 - 2¹⁸ = 21105926827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21106188973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19082801 + ... + 19083906.

It is an arithmetic number, because the mean of its divisors is an integer number (3053336640).

Almost surely, 2^21106188971 is an apocalyptic number.

21106188971 is a deficient number, since it is larger than the sum of its proper divisors (3320504149).

21106188971 is an equidigital number, since it uses as much as digits as its factorization.

21106188971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38166793.

The product of its (nonzero) digits is 48384, while the sum is 44.

The spelling of 21106188971 in words is "twenty-one billion, one hundred six million, one hundred eighty-eight thousand, nine hundred seventy-one".