21271854 has 16 divisors (see below), whose sum is σ = 42590160. Its totient is φ = 7082880.

The previous prime is 21271843. The next prime is 21271883. The reversal of 21271854 is 45817212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7744 + ... + 10124.

It is an arithmetic number, because the mean of its divisors is an integer number (2661885).

Almost surely, 2^21271854 is an apocalyptic number.

21271854 is an abundant number, since it is smaller than the sum of its proper divisors (21318306).

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

21271854 is a wasteful number, since it uses less digits than its factorization.

21271854 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3875.

The product of its digits is 4480, while the sum is 30.

The square root of 21271854 is about 4612.1420186287. The cubic root of 21271854 is about 277.0778322210.

The spelling of 21271854 in words is "twenty-one million, two hundred seventy-one thousand, eight hundred fifty-four".