21672467 has 4 divisors (see below), whose sum is σ = 22947336. Its totient is φ = 20397600.

The previous prime is 21672461. The next prime is 21672481. The reversal of 21672467 is 76427612.

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 21672467 - 2⁶ = 21672403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21672461) 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, 637409 + ... + 637442.

It is an arithmetic number, because the mean of its divisors is an integer number (5736834).

Almost surely, 2^21672467 is an apocalyptic number.

21672467 is a deficient number, since it is larger than the sum of its proper divisors (1274869).

21672467 is a wasteful number, since it uses less digits than its factorization.

21672467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1274868.

The product of its digits is 28224, while the sum is 35.

The square root of 21672467 is about 4655.3696953088. The cubic root of 21672467 is about 278.8064286815.

The spelling of 21672467 in words is "twenty-one million, six hundred seventy-two thousand, four hundred sixty-seven".