1231340405 has 16 divisors (see below), whose sum is σ = 1502582400. Its totient is φ = 968480832.

The previous prime is 1231340393. The next prime is 1231340437. The reversal of 1231340405 is 5040431321.

It is a cyclic number.

It is not a de Polignac number, because 1231340405 - 2²² = 1227146101 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 183296 + ... + 189894.

It is an arithmetic number, because the mean of its divisors is an integer number (93911400).

Almost surely, 2^1231340405 is an apocalyptic number.

It is an amenable number.

1231340405 is a deficient number, since it is larger than the sum of its proper divisors (271241995).

1231340405 is an equidigital number, since it uses as much as digits as its factorization.

1231340405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7228.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 1231340405 is about 35090.4603133102. The cubic root of 1231340405 is about 1071.8303330671.

Adding to 1231340405 its reverse (5040431321), we get a palindrome (6271771726).

The spelling of 1231340405 in words is "one billion, two hundred thirty-one million, three hundred forty thousand, four hundred five".