20538243 has 12 divisors (see below), whose sum is σ = 32363448. Its totient is φ = 12447360.

The previous prime is 20538239. The next prime is 20538283. The reversal of 20538243 is 34283502.

It is not a de Polignac number, because 20538243 - 2² = 20538239 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20538283) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 103630 + ... + 103827.

It is an arithmetic number, because the mean of its divisors is an integer number (2696954).

Almost surely, 2^20538243 is an apocalyptic number.

20538243 is a deficient number, since it is larger than the sum of its proper divisors (11825205).

20538243 is a wasteful number, since it uses less digits than its factorization.

20538243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207474 (or 207471 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 20538243 is about 4531.9138341323. The cubic root of 20538243 is about 273.8552657030.

It can be divided in two parts, 2053 and 8243, that added together give a triangular number (10296 = T₁₄₃).

The spelling of 20538243 in words is "twenty million, five hundred thirty-eight thousand, two hundred forty-three".