21332667 has 4 divisors (see below), whose sum is σ = 28443560. Its totient is φ = 14221776.

The previous prime is 21332653. The next prime is 21332693. The reversal of 21332667 is 76623312.

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

It is not a de Polignac number, because 21332667 - 2⁴ = 21332651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21332567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3555442 + ... + 3555447.

It is an arithmetic number, because the mean of its divisors is an integer number (7110890).

Almost surely, 2^21332667 is an apocalyptic number.

21332667 is a deficient number, since it is larger than the sum of its proper divisors (7110893).

21332667 is an equidigital number, since it uses as much as digits as its factorization.

21332667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7110892.

The product of its digits is 9072, while the sum is 30.

The square root of 21332667 is about 4618.7300202545. The cubic root of 21332667 is about 277.3416221494.

Adding to 21332667 its reverse (76623312), we get a palindrome (97955979).

The spelling of 21332667 in words is "twenty-one million, three hundred thirty-two thousand, six hundred sixty-seven".