21673841 has 8 divisors (see below), whose sum is σ = 24815424. Its totient is φ = 18543600.

The previous prime is 21673837. The next prime is 21673859. The reversal of 21673841 is 14837612.

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 21673841 - 2² = 21673837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21673798 and 21673807.

It is not an unprimeable number, because it can be changed into a prime (21673831) 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, 1766 + ... + 6816.

It is an arithmetic number, because the mean of its divisors is an integer number (3101928).

Almost surely, 2^21673841 is an apocalyptic number.

It is an amenable number.

21673841 is a deficient number, since it is larger than the sum of its proper divisors (3141583).

21673841 is an equidigital number, since it uses as much as digits as its factorization.

21673841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5671.

The product of its digits is 8064, while the sum is 32.

The square root of 21673841 is about 4655.5172644938. The cubic root of 21673841 is about 278.8123205186.

The spelling of 21673841 in words is "twenty-one million, six hundred seventy-three thousand, eight hundred forty-one".