261513233 has 2 divisors, whose sum is σ = 261513234. Its totient is φ = 261513232.

The previous prime is 261513209. The next prime is 261513251. The reversal of 261513233 is 332315162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 146337409 + 115175824 = 12097^2 + 10732^2 .

It is a cyclic number.

It is not a de Polignac number, because 261513233 - 2¹⁴ = 261496849 is a prime.

It is a super-2 number, since 2×261513233² = 136778342068224578, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (261518233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130756616 + 130756617.

It is an arithmetic number, because the mean of its divisors is an integer number (130756617).

Almost surely, 2^261513233 is an apocalyptic number.

It is an amenable number.

261513233 is a deficient number, since it is larger than the sum of its proper divisors (1).

261513233 is an equidigital number, since it uses as much as digits as its factorization.

261513233 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3240, while the sum is 26.

The square root of 261513233 is about 16171.3707829609. The cubic root of 261513233 is about 639.4862682361.

Adding to 261513233 its reverse (332315162), we get a palindrome (593828395).

The spelling of 261513233 in words is "two hundred sixty-one million, five hundred thirteen thousand, two hundred thirty-three".