261279071 has 2 divisors, whose sum is σ = 261279072. Its totient is φ = 261279070.

The previous prime is 261279061. The next prime is 261279097. The reversal of 261279071 is 170972162.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261279071 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261279041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130639535 + 130639536.

It is an arithmetic number, because the mean of its divisors is an integer number (130639536).

Almost surely, 2^261279071 is an apocalyptic number.

261279071 is a deficient number, since it is larger than the sum of its proper divisors (1).

261279071 is an equidigital number, since it uses as much as digits as its factorization.

261279071 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10584, while the sum is 35.

The square root of 261279071 is about 16164.1291444977. The cubic root of 261279071 is about 639.2953434175.

The spelling of 261279071 in words is "two hundred sixty-one million, two hundred seventy-nine thousand, seventy-one".