1131507731 has 4 divisors (see below), whose sum is σ = 1131907464. Its totient is φ = 1131108000.

The previous prime is 1131507721. The next prime is 1131507733. The reversal of 1131507731 is 1377051311.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1377051311 = 37 ⋅37217603.

It is a cyclic number.

It is not a de Polignac number, because 1131507731 - 2⁶ = 1131507667 is a prime.

It is a super-2 number, since 2×1131507731² = 2560619490625536722, 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 = 1131507694 and 1131507703.

It is not an unprimeable number, because it can be changed into a prime (1131507733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 195590 + ... + 201291.

It is an arithmetic number, because the mean of its divisors is an integer number (282976866).

Almost surely, 2^1131507731 is an apocalyptic number.

1131507731 is a deficient number, since it is larger than the sum of its proper divisors (399733).

1131507731 is an equidigital number, since it uses as much as digits as its factorization.

1131507731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399732.

The product of its (nonzero) digits is 2205, while the sum is 29.

The square root of 1131507731 is about 33637.8912983558. The cubic root of 1131507731 is about 1042.0434830802.

The spelling of 1131507731 in words is "one billion, one hundred thirty-one million, five hundred seven thousand, seven hundred thirty-one".