21064467 has 4 divisors (see below), whose sum is σ = 28085960. Its totient is φ = 14042976.

The previous prime is 21064363. The next prime is 21064471. The reversal of 21064467 is 76446012.

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

It is a de Polignac number, because none of the positive numbers 2^k-21064467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21064567) 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, 3510742 + ... + 3510747.

It is an arithmetic number, because the mean of its divisors is an integer number (7021490).

Almost surely, 2^21064467 is an apocalyptic number.

21064467 is a deficient number, since it is larger than the sum of its proper divisors (7021493).

21064467 is an equidigital number, since it uses as much as digits as its factorization.

21064467 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7021492.

The product of its (nonzero) digits is 8064, while the sum is 30.

The square root of 21064467 is about 4589.6042313036. The cubic root of 21064467 is about 276.1744460087.

The spelling of 21064467 in words is "twenty-one million, sixty-four thousand, four hundred sixty-seven".