18530261 has 2 divisors, whose sum is σ = 18530262. Its totient is φ = 18530260.

The previous prime is 18530251. The next prime is 18530269. The reversal of 18530261 is 16203581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14554225 + 3976036 = 3815^2 + 1994^2 .

It is a cyclic number.

It is not a de Polignac number, because 18530261 - 2¹⁴ = 18513877 is a prime.

It is a Chen prime.

It is equal to p_1182950 and since 18530261 and 1182950 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18530261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18530269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9265130 + 9265131.

It is an arithmetic number, because the mean of its divisors is an integer number (9265131).

Almost surely, 2^18530261 is an apocalyptic number.

It is an amenable number.

18530261 is a deficient number, since it is larger than the sum of its proper divisors (1).

18530261 is an equidigital number, since it uses as much as digits as its factorization.

18530261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 18530261 is about 4304.6789659625. The cubic root of 18530261 is about 264.6227502617.

The spelling of 18530261 in words is "eighteen million, five hundred thirty thousand, two hundred sixty-one".