21674231 has 4 divisors (see below), whose sum is σ = 22815000. Its totient is φ = 20533464.

The previous prime is 21674227. The next prime is 21674249. The reversal of 21674231 is 13247612.

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 21674231 - 2² = 21674227 is a prime.

It is a super-2 number, since 2×21674231² = 939544578882722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21674231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21674221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 570356 + ... + 570393.

It is an arithmetic number, because the mean of its divisors is an integer number (5703750).

Almost surely, 2^21674231 is an apocalyptic number.

21674231 is a deficient number, since it is larger than the sum of its proper divisors (1140769).

21674231 is a wasteful number, since it uses less digits than its factorization.

21674231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1140768.

The product of its digits is 2016, while the sum is 26.

The square root of 21674231 is about 4655.5591500914. The cubic root of 21674231 is about 278.8139928288.

It can be divided in two parts, 216 and 74231, that added together give a palindrome (74447).

The spelling of 21674231 in words is "twenty-one million, six hundred seventy-four thousand, two hundred thirty-one".