1291787042 has 32 divisors (see below), whose sum is σ = 2488534272. Its totient is φ = 488816064.

The previous prime is 1291787039. The next prime is 1291787069. The reversal of 1291787042 is 2407871921.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 150113 + ... + 158484.

It is an arithmetic number, because the mean of its divisors is an integer number (77766696).

Almost surely, 2^1291787042 is an apocalyptic number.

1291787042 is a deficient number, since it is larger than the sum of its proper divisors (1196747230).

1291787042 is a wasteful number, since it uses less digits than its factorization.

1291787042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308642.

The product of its (nonzero) digits is 56448, while the sum is 41.

The square root of 1291787042 is about 35941.4390641221. The cubic root of 1291787042 is about 1089.0896762169.

The spelling of 1291787042 in words is "one billion, two hundred ninety-one million, seven hundred eighty-seven thousand, forty-two".