21472329 has 4 divisors (see below), whose sum is σ = 28629776. Its totient is φ = 14314884.

The previous prime is 21472313. The next prime is 21472379. The reversal of 21472329 is 92327412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21472329 - 2⁴ = 21472313 is a prime.

It is a super-2 number, since 2×21472329² = 922121825368482, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21472296 and 21472305.

It is not an unprimeable number, because it can be changed into a prime (21472379) 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, 3578719 + ... + 3578724.

It is an arithmetic number, because the mean of its divisors is an integer number (7157444).

Almost surely, 2^21472329 is an apocalyptic number.

It is an amenable number.

21472329 is a deficient number, since it is larger than the sum of its proper divisors (7157447).

21472329 is an equidigital number, since it uses as much as digits as its factorization.

21472329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7157446.

The product of its digits is 6048, while the sum is 30.

The square root of 21472329 is about 4633.8244463941. The cubic root of 21472329 is about 277.9455451196.

The spelling of 21472329 in words is "twenty-one million, four hundred seventy-two thousand, three hundred twenty-nine".