21676147 has 4 divisors (see below), whose sum is σ = 21733720. Its totient is φ = 21618576.

The previous prime is 21676141. The next prime is 21676181. The reversal of 21676147 is 74167612.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21676147 - 2¹⁵ = 21643379 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21676141) 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 3 ways as a sum of consecutive naturals, for example, 28218 + ... + 28975.

It is an arithmetic number, because the mean of its divisors is an integer number (5433430).

Almost surely, 2^21676147 is an apocalyptic number.

21676147 is a deficient number, since it is larger than the sum of its proper divisors (57573).

21676147 is an equidigital number, since it uses as much as digits as its factorization.

21676147 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57572.

The product of its digits is 14112, while the sum is 34.

The square root of 21676147 is about 4655.7649210414. The cubic root of 21676147 is about 278.8222082970.

The spelling of 21676147 in words is "twenty-one million, six hundred seventy-six thousand, one hundred forty-seven".