21064258 has 8 divisors (see below), whose sum is σ = 33455052. Its totient is φ = 9912576.

The previous prime is 21064249. The next prime is 21064259. The reversal of 21064258 is 85246012.

It can be written as a sum of positive squares in 2 ways, for example, as 20403289 + 660969 = 4517^2 + 813^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21064259) 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, 309735 + ... + 309802.

Almost surely, 2^21064258 is an apocalyptic number.

21064258 is a deficient number, since it is larger than the sum of its proper divisors (12390794).

21064258 is a wasteful number, since it uses less digits than its factorization.

21064258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619556.

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 21064258 is about 4589.5814623994. The cubic root of 21064258 is about 276.1735326119.

The spelling of 21064258 in words is "twenty-one million, sixty-four thousand, two hundred fifty-eight".