2145131231 has 4 divisors (see below), whose sum is σ = 2152452792. Its totient is φ = 2137809672.

The previous prime is 2145131221. The next prime is 2145131237. The reversal of 2145131231 is 1321315412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2145131231 - 2¹⁴ = 2145114847 is a prime.

It is a super-2 number, since 2×2145131231² = 9203175996423150722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2145131197 and 2145131206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2145131237) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3660341 + ... + 3660926.

It is an arithmetic number, because the mean of its divisors is an integer number (538113198).

Almost surely, 2^2145131231 is an apocalyptic number.

2145131231 is a deficient number, since it is larger than the sum of its proper divisors (7321561).

2145131231 is an equidigital number, since it uses as much as digits as its factorization.

2145131231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7321560.

The product of its digits is 720, while the sum is 23.

The square root of 2145131231 is about 46315.5614345762. The cubic root of 2145131231 is about 1289.6878901596.

Adding to 2145131231 its reverse (1321315412), we get a palindrome (3466446643).

The spelling of 2145131231 in words is "two billion, one hundred forty-five million, one hundred thirty-one thousand, two hundred thirty-one".