21213032 has 8 divisors (see below), whose sum is σ = 39774450. Its totient is φ = 10606512.

The previous prime is 21213029. The next prime is 21213041. The reversal of 21213032 is 23031212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19945156 + 1267876 = 4466^2 + 1126^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 21212998 and 21213016.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1325807 + ... + 1325822.

Almost surely, 2^21213032 is an apocalyptic number.

It is an amenable number.

21213032 is a deficient number, since it is larger than the sum of its proper divisors (18561418).

21213032 is a wasteful number, since it uses less digits than its factorization.

21213032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2651635 (or 2651631 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21213032 is about 4605.7607406378. The cubic root of 21213032 is about 276.8221999302.

Adding to 21213032 its reverse (23031212), we get a palindrome (44244244).

The spelling of 21213032 in words is "twenty-one million, two hundred thirteen thousand, thirty-two".