21032323 has 4 divisors (see below), whose sum is σ = 22650208. Its totient is φ = 19414440.

The previous prime is 21032309. The next prime is 21032329. The reversal of 21032323 is 32323012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21032323 - 2²¹ = 18935171 is a prime.

It is a super-2 number, since 2×21032323² = 884717221552658, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21032297 and 21032306.

It is not an unprimeable number, because it can be changed into a prime (21032329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 808923 + ... + 808948.

It is an arithmetic number, because the mean of its divisors is an integer number (5662552).

Almost surely, 2^21032323 is an apocalyptic number.

21032323 is a deficient number, since it is larger than the sum of its proper divisors (1617885).

21032323 is a wasteful number, since it uses less digits than its factorization.

21032323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1617884.

The product of its (nonzero) digits is 216, while the sum is 16.

The square root of 21032323 is about 4586.1010673556. The cubic root of 21032323 is about 276.0338954031.

Adding to 21032323 its reverse (32323012), we get a palindrome (53355335).

The spelling of 21032323 in words is "twenty-one million, thirty-two thousand, three hundred twenty-three".