21064506 has 8 divisors (see below), whose sum is σ = 42129024. Its totient is φ = 7021500.

The previous prime is 21064499. The next prime is 21064523. The reversal of 21064506 is 60546012.

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

21064506 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1755370 + ... + 1755381.

It is an arithmetic number, because the mean of its divisors is an integer number (5266128).

Almost surely, 2^21064506 is an apocalyptic number.

21064506 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21064506 is a wasteful number, since it uses less digits than its factorization.

21064506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3510756.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 21064506 is about 4589.6084800340. The cubic root of 21064506 is about 276.1746164505.

The spelling of 21064506 in words is "twenty-one million, sixty-four thousand, five hundred six".