131235405 has 16 divisors (see below), whose sum is σ = 239973504. Its totient is φ = 59993280.

The previous prime is 131235397. The next prime is 131235437. The reversal of 131235405 is 504532131.

It is not a de Polignac number, because 131235405 - 2³ = 131235397 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 624826 + ... + 625035.

It is an arithmetic number, because the mean of its divisors is an integer number (14998344).

Almost surely, 2^131235405 is an apocalyptic number.

131235405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

131235405 is a deficient number, since it is larger than the sum of its proper divisors (108738099).

131235405 is a wasteful number, since it uses less digits than its factorization.

131235405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1249876.

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 131235405 is about 11455.8022416590. The cubic root of 131235405 is about 508.1793404967.

Adding to 131235405 its reverse (504532131), we get a palindrome (635767536).

It can be divided in two parts, 13123 and 5405, that added together give a triangular number (18528 = T₁₉₂).

The spelling of 131235405 in words is "one hundred thirty-one million, two hundred thirty-five thousand, four hundred five".