21627673 has 4 divisors (see below), whose sum is σ = 21640320. Its totient is φ = 21615028.

The previous prime is 21627629. The next prime is 21627679. The reversal of 21627673 is 37672612.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-21627673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21627679) 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, 3265 + ... + 7342.

It is an arithmetic number, because the mean of its divisors is an integer number (5410080).

Almost surely, 2^21627673 is an apocalyptic number.

It is an amenable number.

21627673 is a deficient number, since it is larger than the sum of its proper divisors (12647).

21627673 is a wasteful number, since it uses less digits than its factorization.

21627673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12646.

The product of its digits is 21168, while the sum is 34.

The square root of 21627673 is about 4650.5562032944. The cubic root of 21627673 is about 278.6142113810.

It can be divided in two parts, 216 and 27673, that added together give a square (27889 = 167²).

The spelling of 21627673 in words is "twenty-one million, six hundred twenty-seven thousand, six hundred seventy-three".