18236501 has 2 divisors, whose sum is σ = 18236502. Its totient is φ = 18236500.

The previous prime is 18236497. The next prime is 18236503. The reversal of 18236501 is 10563281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9296401 + 8940100 = 3049^2 + 2990^2 .

It is a cyclic number.

It is not a de Polignac number, because 18236501 - 2² = 18236497 is a prime.

Together with 18236503, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18236503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9118250 + 9118251.

It is an arithmetic number, because the mean of its divisors is an integer number (9118251).

Almost surely, 2^18236501 is an apocalyptic number.

It is an amenable number.

18236501 is a deficient number, since it is larger than the sum of its proper divisors (1).

18236501 is an equidigital number, since it uses as much as digits as its factorization.

18236501 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 18236501 is about 4270.4216419459. The cubic root of 18236501 is about 263.2169413882.

Adding to 18236501 its reverse (10563281), we get a palindrome (28799782).

The spelling of 18236501 in words is "eighteen million, two hundred thirty-six thousand, five hundred one".