261612427 has 2 divisors, whose sum is σ = 261612428. Its totient is φ = 261612426.

The previous prime is 261612413. The next prime is 261612437. The reversal of 261612427 is 724216162.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261612427 is a prime.

It is not a weakly prime, because it can be changed into another prime (261612437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130806213 + 130806214.

It is an arithmetic number, because the mean of its divisors is an integer number (130806214).

Almost surely, 2^261612427 is an apocalyptic number.

261612427 is a deficient number, since it is larger than the sum of its proper divisors (1).

261612427 is an equidigital number, since it uses as much as digits as its factorization.

261612427 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 31.

The square root of 261612427 is about 16174.4374554418. The cubic root of 261612427 is about 639.5671120512.

Adding to 261612427 its reverse (724216162), we get a palindrome (985828589).

The spelling of 261612427 in words is "two hundred sixty-one million, six hundred twelve thousand, four hundred twenty-seven".