1205131515 has 16 divisors (see below), whose sum is σ = 2203669248. Its totient is φ = 550917216.

The previous prime is 1205131451. The next prime is 1205131517. The reversal of 1205131515 is 5151315021.

It is not a de Polignac number, because 1205131515 - 2⁶ = 1205131451 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1205131517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5738617 + ... + 5738826.

It is an arithmetic number, because the mean of its divisors is an integer number (137729328).

Almost surely, 2^1205131515 is an apocalyptic number.

1205131515 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1205131515 is a deficient number, since it is larger than the sum of its proper divisors (998537733).

1205131515 is a wasteful number, since it uses less digits than its factorization.

1205131515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11477458.

The product of its (nonzero) digits is 750, while the sum is 24.

The square root of 1205131515 is about 34715.0041768685. The cubic root of 1205131515 is about 1064.1711508250.

Adding to 1205131515 its reverse (5151315021), we get a palindrome (6356446536).

The spelling of 1205131515 in words is "one billion, two hundred five million, one hundred thirty-one thousand, five hundred fifteen".