1121255431 has 4 divisors (see below), whose sum is σ = 1121344272. Its totient is φ = 1121166592.

The previous prime is 1121255419. The next prime is 1121255459. The reversal of 1121255431 is 1345521211.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1345521211 = 1307 ⋅1029473.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1121255431 is a prime.

It is a super-2 number, since 2×1121255431² = 2514427483093991522, 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 = 1121255396 and 1121255405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121253431) 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, 21571 + ... + 52036.

It is an arithmetic number, because the mean of its divisors is an integer number (280336068).

Almost surely, 2^1121255431 is an apocalyptic number.

1121255431 is a deficient number, since it is larger than the sum of its proper divisors (88841).

1121255431 is an equidigital number, since it uses as much as digits as its factorization.

1121255431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88840.

The product of its digits is 1200, while the sum is 25.

The square root of 1121255431 is about 33485.1523962487. The cubic root of 1121255431 is about 1038.8867003634.

Adding to 1121255431 its reverse (1345521211), we get a palindrome (2466776642).

The spelling of 1121255431 in words is "one billion, one hundred twenty-one million, two hundred fifty-five thousand, four hundred thirty-one".