261713381 has 2 divisors, whose sum is σ = 261713382. Its totient is φ = 261713380.

The previous prime is 261713329. The next prime is 261713399. The reversal of 261713381 is 183317162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 158508100 + 103205281 = 12590^2 + 10159^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261713381 is a prime.

It is a super-2 number, since 2×261713381² = 136987787588902322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261713681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130856690 + 130856691.

It is an arithmetic number, because the mean of its divisors is an integer number (130856691).

Almost surely, 2^261713381 is an apocalyptic number.

It is an amenable number.

261713381 is a deficient number, since it is larger than the sum of its proper divisors (1).

261713381 is an equidigital number, since it uses as much as digits as its factorization.

261713381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 32.

The square root of 261713381 is about 16177.5579430271. The cubic root of 261713381 is about 639.6493692991.

The spelling of 261713381 in words is "two hundred sixty-one million, seven hundred thirteen thousand, three hundred eighty-one".