21171271158 has 60 divisors (see below), whose sum is σ = 47724802092. Its totient is φ = 7014719880.

The previous prime is 21171271141. The next prime is 21171271207. The reversal of 21171271158 is 85117217112.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 26900841 + ... + 26901627.

Almost surely, 2^21171271158 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21171271158, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23862401046).

21171271158 is an abundant number, since it is smaller than the sum of its proper divisors (26553530934).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21171271158 is an frugal number, since it uses more digits than its factorization.

21171271158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1799 (or 1003 counting only the distinct ones).

The product of its digits is 7840, while the sum is 36.

The spelling of 21171271158 in words is "twenty-one billion, one hundred seventy-one million, two hundred seventy-one thousand, one hundred fifty-eight".