21297741 has 8 divisors (see below), whose sum is σ = 28421664. Its totient is φ = 14186160.

The previous prime is 21297733. The next prime is 21297751. The reversal of 21297741 is 14779212.

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

It is not a de Polignac number, because 21297741 - 2³ = 21297733 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21297751) 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, 2275 + ... + 6911.

It is an arithmetic number, because the mean of its divisors is an integer number (3552708).

Almost surely, 2^21297741 is an apocalyptic number.

It is an amenable number.

21297741 is a deficient number, since it is larger than the sum of its proper divisors (7123923).

21297741 is a wasteful number, since it uses less digits than its factorization.

21297741 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6171.

The product of its digits is 7056, while the sum is 33.

The square root of 21297741 is about 4614.9475619989. The cubic root of 21297741 is about 277.1901842233.

It can be divided in two parts, 2129 and 7741, that added together give a triangular number (9870 = T₁₄₀).

The spelling of 21297741 in words is "twenty-one million, two hundred ninety-seven thousand, seven hundred forty-one".