16538261 has 2 divisors, whose sum is σ = 16538262. Its totient is φ = 16538260.

The previous prime is 16538251. The next prime is 16538267. The reversal of 16538261 is 16283561.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11015761 + 5522500 = 3319^2 + 2350^2 .

It is a cyclic number.

It is not a de Polignac number, because 16538261 - 2¹⁰ = 16537237 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16538267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8269130 + 8269131.

It is an arithmetic number, because the mean of its divisors is an integer number (8269131).

Almost surely, 2^16538261 is an apocalyptic number.

It is an amenable number.

16538261 is a deficient number, since it is larger than the sum of its proper divisors (1).

16538261 is an equidigital number, since it uses as much as digits as its factorization.

16538261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 32.

The square root of 16538261 is about 4066.7260788010. The cubic root of 16538261 is about 254.7787957368.

The spelling of 16538261 in words is "sixteen million, five hundred thirty-eight thousand, two hundred sixty-one".