21032444 has 12 divisors (see below), whose sum is σ = 36966384. Its totient is φ = 10470624.

The previous prime is 21032441. The next prime is 21032447. The reversal of 21032444 is 44423012.

It is an interprime number because it is at equal distance from previous prime (21032441) and next prime (21032447).

It is a super-2 number, since 2×21032444² = 884727401226272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21032441) 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, 10352 + ... + 12215.

It is an arithmetic number, because the mean of its divisors is an integer number (3080532).

Almost surely, 2^21032444 is an apocalyptic number.

It is an amenable number.

21032444 is a deficient number, since it is larger than the sum of its proper divisors (15933940).

21032444 is a wasteful number, since it uses less digits than its factorization.

21032444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22804 (or 22802 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 21032444 is about 4586.1142593703. The cubic root of 21032444 is about 276.0344247476.

Adding to 21032444 its reverse (44423012), we get a palindrome (65455456).

The spelling of 21032444 in words is "twenty-one million, thirty-two thousand, four hundred forty-four".