21160775 has 12 divisors (see below), whose sum is σ = 27621000. Its totient is φ = 16037280.

The previous prime is 21160771. The next prime is 21160787. The reversal of 21160775 is 57706112.

It is not a de Polignac number, because 21160775 - 2² = 21160771 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21160771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21800 + ... + 22749.

It is an arithmetic number, because the mean of its divisors is an integer number (2301750).

Almost surely, 2^21160775 is an apocalyptic number.

21160775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21160775 is a deficient number, since it is larger than the sum of its proper divisors (6460225).

21160775 is a wasteful number, since it uses less digits than its factorization.

21160775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44578 (or 44573 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 29.

The square root of 21160775 is about 4600.0842383591. The cubic root of 21160775 is about 276.5947015289.

Adding to 21160775 its reverse (57706112), we get a palindrome (78866887).

The spelling of 21160775 in words is "twenty-one million, one hundred sixty thousand, seven hundred seventy-five".