21331674 has 80 divisors (see below), whose sum is σ = 58869888. Its totient is φ = 5622048.

The previous prime is 21331669. The next prime is 21331679. The reversal of 21331674 is 47613312.

It is an interprime number because it is at equal distance from previous prime (21331669) and next prime (21331679).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21331679) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 14019 + ... + 15465.

Almost surely, 2^21331674 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21331674, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29434944).

21331674 is an abundant number, since it is smaller than the sum of its proper divisors (37538214).

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

21331674 is a wasteful number, since it uses less digits than its factorization.

21331674 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1481 (or 1472 counting only the distinct ones).

The product of its digits is 3024, while the sum is 27.

The square root of 21331674 is about 4618.6225219214. The cubic root of 21331674 is about 277.3373188196.

Adding to 21331674 its reverse (47613312), we get a palindrome (68944986).

The spelling of 21331674 in words is "twenty-one million, three hundred thirty-one thousand, six hundred seventy-four".