21326546 has 4 divisors (see below), whose sum is σ = 31989822. Its totient is φ = 10663272.

The previous prime is 21326537. The next prime is 21326561. The reversal of 21326546 is 64562312.

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

It can be written as a sum of positive squares in only one way, i.e., 21114025 + 212521 = 4595^2 + 461^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5331635 + ... + 5331638.

Almost surely, 2^21326546 is an apocalyptic number.

21326546 is a deficient number, since it is larger than the sum of its proper divisors (10663276).

21326546 is a wasteful number, since it uses less digits than its factorization.

21326546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10663275.

The product of its digits is 8640, while the sum is 29.

The square root of 21326546 is about 4618.0673446800. The cubic root of 21326546 is about 277.3150936573.

Adding to 21326546 its reverse (64562312), we get a palindrome (85888858).

The spelling of 21326546 in words is "twenty-one million, three hundred twenty-six thousand, five hundred forty-six".