21748331 has 8 divisors (see below), whose sum is σ = 24974400. Its totient is φ = 18730440.

The previous prime is 21748313. The next prime is 21748333. The reversal of 21748331 is 13384712.

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 21748331 - 2¹⁴ = 21731947 is a prime.

It is a super-2 number, since 2×21748331² = 945979802571122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21748294 and 21748303.

It is not an unprimeable number, because it can be changed into a prime (21748333) 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, 51821 + ... + 52238.

It is an arithmetic number, because the mean of its divisors is an integer number (3121800).

Almost surely, 2^21748331 is an apocalyptic number.

21748331 is a deficient number, since it is larger than the sum of its proper divisors (3226069).

21748331 is a wasteful number, since it uses less digits than its factorization.

21748331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104089.

The product of its digits is 4032, while the sum is 29.

The square root of 21748331 is about 4663.5105875295. The cubic root of 21748331 is about 279.1313684436.

The spelling of 21748331 in words is "twenty-one million, seven hundred forty-eight thousand, three hundred thirty-one".