21116172371 has 4 divisors (see below), whose sum is σ = 24132768432. Its totient is φ = 18099576312.

The previous prime is 21116172353. The next prime is 21116172397. The reversal of 21116172371 is 17327161112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21116172371 - 2¹⁴ = 21116155987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21116172871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1508298020 + ... + 1508298033.

It is an arithmetic number, because the mean of its divisors is an integer number (6033192108).

Almost surely, 2^21116172371 is an apocalyptic number.

21116172371 is a deficient number, since it is larger than the sum of its proper divisors (3016596061).

21116172371 is an equidigital number, since it uses as much as digits as its factorization.

21116172371 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3016596060.

The product of its digits is 3528, while the sum is 32.

The spelling of 21116172371 in words is "twenty-one billion, one hundred sixteen million, one hundred seventy-two thousand, three hundred seventy-one".