21267629 has 4 divisors (see below), whose sum is σ = 22518684. Its totient is φ = 20016576.

The previous prime is 21267619. The next prime is 21267679. The reversal of 21267629 is 92676212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15132100 + 6135529 = 3890^2 + 2477^2 .

It is a cyclic number.

It is not a de Polignac number, because 21267629 - 2⁴ = 21267613 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 (21267619) 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, 625502 + ... + 625535.

It is an arithmetic number, because the mean of its divisors is an integer number (5629671).

Almost surely, 2^21267629 is an apocalyptic number.

It is an amenable number.

21267629 is a deficient number, since it is larger than the sum of its proper divisors (1251055).

21267629 is a wasteful number, since it uses less digits than its factorization.

21267629 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1251054.

The product of its digits is 18144, while the sum is 35.

The square root of 21267629 is about 4611.6839657548. The cubic root of 21267629 is about 277.0594866746.

The spelling of 21267629 in words is "twenty-one million, two hundred sixty-seven thousand, six hundred twenty-nine".