1235131261 has 24 divisors (see below), whose sum is σ = 1540737024. Its totient is φ = 969433920.

The previous prime is 1235131259. The next prime is 1235131279. The reversal of 1235131261 is 1621315321.

It is a happy number.

It is not a de Polignac number, because 1235131261 - 2¹ = 1235131259 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1235131061) 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 23 ways as a sum of consecutive naturals, for example, 146131 + ... + 154351.

It is an arithmetic number, because the mean of its divisors is an integer number (64197376).

Almost surely, 2^1235131261 is an apocalyptic number.

It is an amenable number.

1235131261 is a deficient number, since it is larger than the sum of its proper divisors (305605763).

1235131261 is a wasteful number, since it uses less digits than its factorization.

1235131261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8381 (or 8368 counting only the distinct ones).

The product of its digits is 1080, while the sum is 25.

The square root of 1235131261 is about 35144.4342819742. The cubic root of 1235131261 is about 1072.9291334433.

Adding to 1235131261 its reverse (1621315321), we get a palindrome (2856446582).

It can be divided in two parts, 1235 and 131261, that added together give a square (132496 = 364²).

The spelling of 1235131261 in words is "one billion, two hundred thirty-five million, one hundred thirty-one thousand, two hundred sixty-one".