1205311231 has 2 divisors, whose sum is σ = 1205311232. Its totient is φ = 1205311230.

The previous prime is 1205311201. The next prime is 1205311277. The reversal of 1205311231 is 1321135021.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1205311231 - 2¹³ = 1205303039 is a prime.

It is a super-2 number, since 2×1205311231² = 2905550327149470722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1205311199 and 1205311208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1205311201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602655615 + 602655616.

It is an arithmetic number, because the mean of its divisors is an integer number (602655616).

Almost surely, 2^1205311231 is an apocalyptic number.

1205311231 is a deficient number, since it is larger than the sum of its proper divisors (1).

1205311231 is an equidigital number, since it uses as much as digits as its factorization.

1205311231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 1205311231 is about 34717.5925288606. The cubic root of 1205311231 is about 1064.2240465945.

Adding to 1205311231 its reverse (1321135021), we get a palindrome (2526446252).

The spelling of 1205311231 in words is "one billion, two hundred five million, three hundred eleven thousand, two hundred thirty-one".