261031 has 2 divisors, whose sum is σ = 261032. Its totient is φ = 261030.

The previous prime is 261017. The next prime is 261043. The reversal of 261031 is 130162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261031 - 2⁵ = 260999 is a prime.

It is a super-2 number, since 2×261031² = 136274365922, 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 (261011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130515 + 130516.

It is an arithmetic number, because the mean of its divisors is an integer number (130516).

2²⁶¹⁰³¹ is an apocalyptic number.

261031 is a deficient number, since it is larger than the sum of its proper divisors (1).

261031 is an equidigital number, since it uses as much as digits as its factorization.

261031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 261031 is about 510.9119297883. The cubic root of 261031 is about 63.9092953367.

Adding to 261031 its reverse (130162), we get a palindrome (391193).

The spelling of 261031 in words is "two hundred sixty-one thousand, thirty-one".