21749332 has 24 divisors (see below), whose sum is σ = 42053760. Its totient is φ = 9759360.

The previous prime is 21749323. The next prime is 21749353. The reversal of 21749332 is 23394712.

It is a junction number, because it is equal to n+sod(n) for n = 21749294 and 21749303.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 348 + ... + 6604.

It is an arithmetic number, because the mean of its divisors is an integer number (1752240).

Almost surely, 2^21749332 is an apocalyptic number.

21749332 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21749332 is a deficient number, since it is larger than the sum of its proper divisors (20304428).

21749332 is a wasteful number, since it uses less digits than its factorization.

21749332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6351 (or 6349 counting only the distinct ones).

The product of its digits is 9072, while the sum is 31.

The square root of 21749332 is about 4663.6179088772. The cubic root of 21749332 is about 279.1356508598.

The spelling of 21749332 in words is "twenty-one million, seven hundred forty-nine thousand, three hundred thirty-two".