21672319 has 2 divisors, whose sum is σ = 21672320. Its totient is φ = 21672318.

The previous prime is 21672271. The next prime is 21672323. The reversal of 21672319 is 91327612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21672319 - 2⁷ = 21672191 is a prime.

It is a super-2 number, since 2×21672319² = 939378821675522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21672349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10836159 + 10836160.

It is an arithmetic number, because the mean of its divisors is an integer number (10836160).

Almost surely, 2^21672319 is an apocalyptic number.

21672319 is a deficient number, since it is larger than the sum of its proper divisors (1).

21672319 is an equidigital number, since it uses as much as digits as its factorization.

21672319 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 31.

The square root of 21672319 is about 4655.3537996591. The cubic root of 21672319 is about 278.8057940291.

The spelling of 21672319 in words is "twenty-one million, six hundred seventy-two thousand, three hundred nineteen".