21023732 has 12 divisors (see below), whose sum is σ = 37647456. Its totient is φ = 10267320.

The previous prime is 21023731. The next prime is 21023741. The reversal of 21023732 is 23732012.

It is a hoax number, since the sum of its digits (20) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21023731) 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, 60944 + ... + 61287.

It is an arithmetic number, because the mean of its divisors is an integer number (3137288).

Almost surely, 2^21023732 is an apocalyptic number.

It is an amenable number.

21023732 is a deficient number, since it is larger than the sum of its proper divisors (16623724).

21023732 is a wasteful number, since it uses less digits than its factorization.

21023732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122278 (or 122276 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 21023732 is about 4585.1643372948. The cubic root of 21023732 is about 275.9963067489.

Adding to 21023732 its reverse (23732012), we get a palindrome (44755744).

The spelling of 21023732 in words is "twenty-one million, twenty-three thousand, seven hundred thirty-two".