21673361 has 8 divisors (see below), whose sum is σ = 22361664. Its totient is φ = 20995920.

The previous prime is 21673339. The next prime is 21673367. The reversal of 21673361 is 16337612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21673361 - 2¹⁰ = 21672337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21673367) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1436 + ... + 6738.

It is an arithmetic number, because the mean of its divisors is an integer number (2795208).

Almost surely, 2^21673361 is an apocalyptic number.

It is an amenable number.

21673361 is a deficient number, since it is larger than the sum of its proper divisors (688303).

21673361 is an equidigital number, since it uses as much as digits as its factorization.

21673361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5431.

The product of its digits is 4536, while the sum is 29.

The square root of 21673361 is about 4655.4657124717. The cubic root of 21673361 is about 278.8102622632.

The spelling of 21673361 in words is "twenty-one million, six hundred seventy-three thousand, three hundred sixty-one".