21066053 has 4 divisors (see below), whose sum is σ = 21263040. Its totient is φ = 20869068.

The previous prime is 21066049. The next prime is 21066107. The reversal of 21066053 is 35066012.

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 a cyclic number.

It is not a de Polignac number, because 21066053 - 2² = 21066049 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21066013) 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, 98333 + ... + 98546.

It is an arithmetic number, because the mean of its divisors is an integer number (5315760).

Almost surely, 2^21066053 is an apocalyptic number.

It is an amenable number.

21066053 is a deficient number, since it is larger than the sum of its proper divisors (196987).

21066053 is a wasteful number, since it uses less digits than its factorization.

21066053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196986.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 21066053 is about 4589.7770098339. Note that the first 3 decimals coincide. The cubic root of 21066053 is about 276.1813771388.

The spelling of 21066053 in words is "twenty-one million, sixty-six thousand, fifty-three".