21694432 has 48 divisors (see below), whose sum is σ = 44643312. Its totient is φ = 10368000.

The previous prime is 21694429. The next prime is 21694433. The reversal of 21694432 is 23449612.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21694394 and 21694403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21694433) by changing a digit.

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, 86307 + ... + 86557.

It is an arithmetic number, because the mean of its divisors is an integer number (930069).

Almost surely, 2^21694432 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21694432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22321656).

21694432 is an abundant number, since it is smaller than the sum of its proper divisors (22948880).

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

21694432 is a wasteful number, since it uses less digits than its factorization.

21694432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371 (or 363 counting only the distinct ones).

The product of its digits is 10368, while the sum is 31.

The square root of 21694432 is about 4657.7282016022. The cubic root of 21694432 is about 278.9005867898.

The spelling of 21694432 in words is "twenty-one million, six hundred ninety-four thousand, four hundred thirty-two".