21092573 has 4 divisors (see below), whose sum is σ = 21607068. Its totient is φ = 20578080.

The previous prime is 21092567. The next prime is 21092579. The reversal of 21092573 is 37529012.

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

It is an interprime number because it is at equal distance from previous prime (21092567) and next prime (21092579).

It can be written as a sum of positive squares in 2 ways, for example, as 10582009 + 10510564 = 3253^2 + 3242^2 .

It is a cyclic number.

It is not a de Polignac number, because 21092573 - 2⁴ = 21092557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21092579) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 257186 + ... + 257267.

It is an arithmetic number, because the mean of its divisors is an integer number (5401767).

Almost surely, 2^21092573 is an apocalyptic number.

It is an amenable number.

21092573 is a deficient number, since it is larger than the sum of its proper divisors (514495).

21092573 is an equidigital number, since it uses as much as digits as its factorization.

21092573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514494.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 21092573 is about 4592.6651304009. The cubic root of 21092573 is about 276.2972232149.

The spelling of 21092573 in words is "twenty-one million, ninety-two thousand, five hundred seventy-three".