21769165 has 8 divisors (see below), whose sum is σ = 28497888. Its totient is φ = 15832080.

The previous prime is 21769151. The next prime is 21769183. The reversal of 21769165 is 56196712.

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

It is not a de Polignac number, because 21769165 - 2¹⁵ = 21736397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 197847 + ... + 197956.

It is an arithmetic number, because the mean of its divisors is an integer number (3562236).

Almost surely, 2^21769165 is an apocalyptic number.

It is an amenable number.

21769165 is a deficient number, since it is larger than the sum of its proper divisors (6728723).

21769165 is a wasteful number, since it uses less digits than its factorization.

21769165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395819.

The product of its digits is 22680, while the sum is 37.

The square root of 21769165 is about 4665.7437777915. The cubic root of 21769165 is about 279.2204720924.

The spelling of 21769165 in words is "twenty-one million, seven hundred sixty-nine thousand, one hundred sixty-five".