21748369 has 8 divisors (see below), whose sum is σ = 23075840. Its totient is φ = 20439216.

The previous prime is 21748367. The next prime is 21748399. The reversal of 21748369 is 96384712.

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 21748369 - 2¹ = 21748367 is a prime.

It is a super-2 number, since 2×21748369² = 945983108320322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21748361) 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 7 ways as a sum of consecutive naturals, for example, 2094 + ... + 6919.

It is an arithmetic number, because the mean of its divisors is an integer number (2884480).

Almost surely, 2^21748369 is an apocalyptic number.

It is an amenable number.

21748369 is a deficient number, since it is larger than the sum of its proper divisors (1327471).

21748369 is a wasteful number, since it uses less digits than its factorization.

21748369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9159.

The product of its digits is 72576, while the sum is 40.

The square root of 21748369 is about 4663.5146617117. The cubic root of 21748369 is about 279.1315310153.

The spelling of 21748369 in words is "twenty-one million, seven hundred forty-eight thousand, three hundred sixty-nine".