1231215535 has 12 divisors (see below), whose sum is σ = 1623984264. Its totient is φ = 895429040.

The previous prime is 1231215511. The next prime is 1231215613. The reversal of 1231215535 is 5355121321.

It is not a de Polignac number, because 1231215535 - 2¹⁹ = 1230691247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1016929 + ... + 1018138.

It is an arithmetic number, because the mean of its divisors is an integer number (135332022).

Almost surely, 2^1231215535 is an apocalyptic number.

1231215535 is a deficient number, since it is larger than the sum of its proper divisors (392768729).

1231215535 is a wasteful number, since it uses less digits than its factorization.

1231215535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2035094 (or 2035083 counting only the distinct ones).

The product of its digits is 4500, while the sum is 28.

The square root of 1231215535 is about 35088.6810096931. The cubic root of 1231215535 is about 1071.7941004712.

Adding to 1231215535 its reverse (5355121321), we get a palindrome (6586336856).

The spelling of 1231215535 in words is "one billion, two hundred thirty-one million, two hundred fifteen thousand, five hundred thirty-five".