1031131987 has 4 divisors (see below), whose sum is σ = 1031732856. Its totient is φ = 1030531120.

The previous prime is 1031131973. The next prime is 1031131993. The reversal of 1031131987 is 7891311301.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7891311301 = 59 ⋅133751039.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1031131987 is a prime.

It is a super-2 number, since 2×1031131987² = 2126466349229136338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1031131487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 297853 + ... + 301294.

It is an arithmetic number, because the mean of its divisors is an integer number (257933214).

Almost surely, 2^1031131987 is an apocalyptic number.

1031131987 is a deficient number, since it is larger than the sum of its proper divisors (600869).

1031131987 is an equidigital number, since it uses as much as digits as its factorization.

1031131987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 600868.

The product of its (nonzero) digits is 4536, while the sum is 34.

The square root of 1031131987 is about 32111.2439341736. The cubic root of 1031131987 is about 1010.2714647877.

The spelling of 1031131987 in words is "one billion, thirty-one million, one hundred thirty-one thousand, nine hundred eighty-seven".