21162773 has 8 divisors (see below), whose sum is σ = 22715928. Its totient is φ = 19643904.

The previous prime is 21162763. The next prime is 21162787. The reversal of 21162773 is 37726112.

It can be written as a sum of positive squares in 4 ways, for example, as 4986289 + 16176484 = 2233^2 + 4022^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21162773 - 2⁶ = 21162709 is a prime.

It is a super-2 number, since 2×21162773² = 895725922099058, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21162763) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7286 + ... + 9767.

It is an arithmetic number, because the mean of its divisors is an integer number (2839491).

Almost surely, 2^21162773 is an apocalyptic number.

It is an amenable number.

21162773 is a deficient number, since it is larger than the sum of its proper divisors (1553155).

21162773 is a wasteful number, since it uses less digits than its factorization.

21162773 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17143.

The product of its digits is 3528, while the sum is 29.

The square root of 21162773 is about 4600.3014031691. The cubic root of 21162773 is about 276.6034066105.

Adding to 21162773 its reverse (37726112), we get a palindrome (58888885).

The spelling of 21162773 in words is "twenty-one million, one hundred sixty-two thousand, seven hundred seventy-three".