1205310531 has 4 divisors (see below), whose sum is σ = 1607080712. Its totient is φ = 803540352.

The previous prime is 1205310521. The next prime is 1205310541. The reversal of 1205310531 is 1350135021.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1205310521) and next prime (1205310541).

It is not a de Polignac number, because 1205310531 - 2¹⁰ = 1205309507 is a prime.

It is a super-2 number, since 2×1205310531² = 2905546952279003922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1205310498 and 1205310507.

It is not an unprimeable number, because it can be changed into a prime (1205310521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 200885086 + ... + 200885091.

It is an arithmetic number, because the mean of its divisors is an integer number (401770178).

Almost surely, 2^1205310531 is an apocalyptic number.

1205310531 is a deficient number, since it is larger than the sum of its proper divisors (401770181).

1205310531 is an equidigital number, since it uses as much as digits as its factorization.

1205310531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401770180.

The product of its (nonzero) digits is 450, while the sum is 21.

The square root of 1205310531 is about 34717.5824475150. The cubic root of 1205310531 is about 1064.2238405739.

Adding to 1205310531 its reverse (1350135021), we get a palindrome (2555445552).

The spelling of 1205310531 in words is "one billion, two hundred five million, three hundred ten thousand, five hundred thirty-one".