261595153 has 2 divisors, whose sum is σ = 261595154. Its totient is φ = 261595152.

The previous prime is 261595141. The next prime is 261595163. The reversal of 261595153 is 351595162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 239382784 + 22212369 = 15472^2 + 4713^2 .

It is a cyclic number.

It is not a de Polignac number, because 261595153 - 2¹⁷ = 261464081 is a prime.

It is not a weakly prime, because it can be changed into another prime (261595163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130797576 + 130797577.

It is an arithmetic number, because the mean of its divisors is an integer number (130797577).

Almost surely, 2^261595153 is an apocalyptic number.

It is an amenable number.

261595153 is a deficient number, since it is larger than the sum of its proper divisors (1).

261595153 is an equidigital number, since it uses as much as digits as its factorization.

261595153 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40500, while the sum is 37.

The square root of 261595153 is about 16173.9034558761. The cubic root of 261595153 is about 639.5530350881.

Subtracting 261595153 from its reverse (351595162), we obtain a palindrome (90000009).

The spelling of 261595153 in words is "two hundred sixty-one million, five hundred ninety-five thousand, one hundred fifty-three".