21267316 has 12 divisors (see below), whose sum is σ = 42534688. Its totient is φ = 9114552.

The previous prime is 21267263. The next prime is 21267371. The reversal of 21267316 is 61376212.

21267316 is an admirable number.

It is a Harshad number since it is a multiple of its sum of digits (28), and also a Moran number because the ratio is a prime number: 759547 = 21267316 / (2 + 1 + 2 + 6 + 7 + 3 + 1 + 6).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 379746 + ... + 379801.

Almost surely, 2^21267316 is an apocalyptic number.

It is an amenable number.

21267316 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21267316 is a wasteful number, since it uses less digits than its factorization.

21267316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 759558 (or 759556 counting only the distinct ones).

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

The square root of 21267316 is about 4611.6500300868. The cubic root of 21267316 is about 277.0581274877.

It can be divided in two parts, 212 and 67316, that added together give a triangular number (67528 = T₃₆₇).

The spelling of 21267316 in words is "twenty-one million, two hundred sixty-seven thousand, three hundred sixteen".