21267361 has 4 divisors (see below), whose sum is σ = 21280000. Its totient is φ = 21254724.

The previous prime is 21267263. The next prime is 21267371. The reversal of 21267361 is 16376212.

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 a cyclic number.

It is not a de Polignac number, because 21267361 - 2⁹ = 21266849 is a prime.

It is a super-3 number, since 3×21267361³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21267371) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3321 + ... + 7318.

It is an arithmetic number, because the mean of its divisors is an integer number (5320000).

Almost surely, 2^21267361 is an apocalyptic number.

It is an amenable number.

21267361 is a deficient number, since it is larger than the sum of its proper divisors (12639).

21267361 is a wasteful number, since it uses less digits than its factorization.

21267361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12638.

The product of its digits is 3024, while the sum is 28.

The square root of 21267361 is about 4611.6549090321. The cubic root of 21267361 is about 277.0583228988.

The spelling of 21267361 in words is "twenty-one million, two hundred sixty-seven thousand, three hundred sixty-one".