538636261 has 2 divisors, whose sum is σ = 538636262. Its totient is φ = 538636260.

The previous prime is 538636243. The next prime is 538636303. The reversal of 538636261 is 162636835.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 276390625 + 262245636 = 16625^2 + 16194^2 .

It is a cyclic number.

It is not a de Polignac number, because 538636261 - 2¹⁵ = 538603493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (538636201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 269318130 + 269318131.

It is an arithmetic number, because the mean of its divisors is an integer number (269318131).

Almost surely, 2^538636261 is an apocalyptic number.

It is an amenable number.

538636261 is a deficient number, since it is larger than the sum of its proper divisors (1).

538636261 is an equidigital number, since it uses as much as digits as its factorization.

538636261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 40.

The square root of 538636261 is about 23208.5385364956. The cubic root of 538636261 is about 813.6391965086.

The spelling of 538636261 in words is "five hundred thirty-eight million, six hundred thirty-six thousand, two hundred sixty-one".