21992773 has 4 divisors (see below), whose sum is σ = 23992128. Its totient is φ = 19993420.

The previous prime is 21992771. The next prime is 21992797. The reversal of 21992773 is 37729912.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21992773 - 2¹ = 21992771 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21992771) 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, 999661 + ... + 999682.

It is an arithmetic number, because the mean of its divisors is an integer number (5998032).

Almost surely, 2^21992773 is an apocalyptic number.

It is an amenable number.

21992773 is a deficient number, since it is larger than the sum of its proper divisors (1999355).

21992773 is a wasteful number, since it uses less digits than its factorization.

21992773 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1999354.

The product of its digits is 47628, while the sum is 40.

The square root of 21992773 is about 4689.6452957553. The cubic root of 21992773 is about 280.1732473745.

The spelling of 21992773 in words is "twenty-one million, nine hundred ninety-two thousand, seven hundred seventy-three".