1131213145 has 4 divisors (see below), whose sum is σ = 1357455780. Its totient is φ = 904970512.

The previous prime is 1131213143. The next prime is 1131213197. The reversal of 1131213145 is 5413121311.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5413121311 = 13 ⋅416393947.

It can be written as a sum of positive squares in 2 ways, for example, as 815902096 + 315311049 = 28564^2 + 17757^2 .

It is a cyclic number.

It is not a de Polignac number, because 1131213145 - 2¹ = 1131213143 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1131213143) 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, 113121310 + ... + 113121319.

It is an arithmetic number, because the mean of its divisors is an integer number (339363945).

Almost surely, 2^1131213145 is an apocalyptic number.

It is an amenable number.

1131213145 is a deficient number, since it is larger than the sum of its proper divisors (226242635).

1131213145 is an equidigital number, since it uses as much as digits as its factorization.

1131213145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226242634.

The product of its digits is 360, while the sum is 22.

The square root of 1131213145 is about 33633.5122311066. The cubic root of 1131213145 is about 1041.9530438498.

Adding to 1131213145 its reverse (5413121311), we get a palindrome (6544334456).

The spelling of 1131213145 in words is "one billion, one hundred thirty-one million, two hundred thirteen thousand, one hundred forty-five".