21274629 has 4 divisors (see below), whose sum is σ = 28366176. Its totient is φ = 14183084.

The previous prime is 21274619. The next prime is 21274639. The reversal of 21274629 is 92647212.

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 an interprime number because it is at equal distance from previous prime (21274619) and next prime (21274639).

It is a cyclic number.

It is not a de Polignac number, because 21274629 - 2⁸ = 21274373 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21274629.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21274619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3545769 + ... + 3545774.

It is an arithmetic number, because the mean of its divisors is an integer number (7091544).

Almost surely, 2^21274629 is an apocalyptic number.

It is an amenable number.

21274629 is a deficient number, since it is larger than the sum of its proper divisors (7091547).

21274629 is an equidigital number, since it uses as much as digits as its factorization.

21274629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7091546.

The product of its digits is 12096, while the sum is 33.

The square root of 21274629 is about 4612.4428451743. The cubic root of 21274629 is about 277.0898803410.

The spelling of 21274629 in words is "twenty-one million, two hundred seventy-four thousand, six hundred twenty-nine".