21267671 has 16 divisors (see below), whose sum is σ = 22619520. Its totient is φ = 19975200.

The previous prime is 21267619. The next prime is 21267679. The reversal of 21267671 is 17676212.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21267671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21267679) 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 15 ways as a sum of consecutive naturals, for example, 210521 + ... + 210621.

It is an arithmetic number, because the mean of its divisors is an integer number (1413720).

Almost surely, 2^21267671 is an apocalyptic number.

21267671 is a deficient number, since it is larger than the sum of its proper divisors (1351849).

21267671 is a wasteful number, since it uses less digits than its factorization.

21267671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286.

The product of its digits is 7056, while the sum is 32.

The square root of 21267671 is about 4611.6885194037. The cubic root of 21267671 is about 277.0596690565.

The spelling of 21267671 in words is "twenty-one million, two hundred sixty-seven thousand, six hundred seventy-one".