21490332 has 24 divisors (see below), whose sum is σ = 50633856. Its totient is φ = 7093488.

The previous prime is 21490319. The next prime is 21490393. The reversal of 21490332 is 23309412.

It is a super-3 number, since 3×21490332³ (a number of 23 digits) contains 333 as substring.

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, 7458 + ... + 9929.

It is an arithmetic number, because the mean of its divisors is an integer number (2109744).

Almost surely, 2^21490332 is an apocalyptic number.

It is an amenable number.

21490332 is an abundant number, since it is smaller than the sum of its proper divisors (29143524).

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

21490332 is a wasteful number, since it uses less digits than its factorization.

21490332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17497 (or 17495 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 21490332 is about 4635.7666032707. The cubic root of 21490332 is about 278.0232025214.

Adding to 21490332 its reverse (23309412), we get a palindrome (44799744).

The spelling of 21490332 in words is "twenty-one million, four hundred ninety thousand, three hundred thirty-two".