21057266 has 8 divisors (see below), whose sum is σ = 31966704. Its totient is φ = 10401700.

The previous prime is 21057247. The next prime is 21057287. The reversal of 21057266 is 66275012.

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

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, 63260 + ... + 63591.

It is an arithmetic number, because the mean of its divisors is an integer number (3995838).

Almost surely, 2^21057266 is an apocalyptic number.

21057266 is a deficient number, since it is larger than the sum of its proper divisors (10909438).

21057266 is a wasteful number, since it uses less digits than its factorization.

21057266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126936.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 21057266 is about 4588.8196739467. The cubic root of 21057266 is about 276.1429718545.

The spelling of 21057266 in words is "twenty-one million, fifty-seven thousand, two hundred sixty-six".