20266538 has 4 divisors (see below), whose sum is σ = 30399810. Its totient is φ = 10133268.

The previous prime is 20266537. The next prime is 20266553. The reversal of 20266538 is 83566202.

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

It can be written as a sum of positive squares in only one way, i.e., 13490929 + 6775609 = 3673^2 + 2603^2 .

It is not an unprimeable number, because it can be changed into a prime (20266531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5066633 + ... + 5066636.

Almost surely, 2^20266538 is an apocalyptic number.

20266538 is a deficient number, since it is larger than the sum of its proper divisors (10133272).

20266538 is a wasteful number, since it uses less digits than its factorization.

20266538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10133271.

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 20266538 is about 4501.8371805297. The cubic root of 20266538 is about 272.6422700684.

The spelling of 20266538 in words is "twenty million, two hundred sixty-six thousand, five hundred thirty-eight".