21740033 has 4 divisors (see below), whose sum is σ = 24845760. Its totient is φ = 18634308.

The previous prime is 21740029. The next prime is 21740051. The reversal of 21740033 is 33004712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21740033 - 2² = 21740029 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21739987 and 21740014.

It is not an unprimeable number, because it can be changed into a prime (21740003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1552853 + ... + 1552866.

It is an arithmetic number, because the mean of its divisors is an integer number (6211440).

Almost surely, 2^21740033 is an apocalyptic number.

It is an amenable number.

21740033 is a deficient number, since it is larger than the sum of its proper divisors (3105727).

21740033 is an equidigital number, since it uses as much as digits as its factorization.

21740033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3105726.

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 21740033 is about 4662.6208295335. The cubic root of 21740033 is about 279.0958633936.

Adding to 21740033 its reverse (33004712), we get a palindrome (54744745).

The spelling of 21740033 in words is "twenty-one million, seven hundred forty thousand, thirty-three".