12231557 has 4 divisors (see below), whose sum is σ = 13172460. Its totient is φ = 11290656.

The previous prime is 12231547. The next prime is 12231563. The reversal of 12231557 is 75513221.

12231557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4800481 + 7431076 = 2191^2 + 2726^2 .

It is not a de Polignac number, because 12231557 - 2⁶ = 12231493 is a prime.

It is a super-2 number, since 2×12231557² = 299221973288498, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12231547) 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, 470432 + ... + 470457.

It is an arithmetic number, because the mean of its divisors is an integer number (3293115).

Almost surely, 2^12231557 is an apocalyptic number.

It is an amenable number.

12231557 is a deficient number, since it is larger than the sum of its proper divisors (940903).

12231557 is an equidigital number, since it uses as much as digits as its factorization.

12231557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 940902.

The product of its digits is 2100, while the sum is 26.

The square root of 12231557 is about 3497.3642932929. The cubic root of 12231557 is about 230.4060690455.

Adding to 12231557 its reverse (75513221), we get a palindrome (87744778).

The spelling of 12231557 in words is "twelve million, two hundred thirty-one thousand, five hundred fifty-seven".