1318910991 has 16 divisors (see below), whose sum is σ = 1807897728. Its totient is φ = 854647200.

The previous prime is 1318910969. The next prime is 1318911019. The reversal of 1318910991 is 1990198131.

It is a happy number.

It is not a de Polignac number, because 1318910991 - 2⁶ = 1318910927 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1318910911) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115656 + ... + 126546.

It is an arithmetic number, because the mean of its divisors is an integer number (112993608).

Almost surely, 2^1318910991 is an apocalyptic number.

1318910991 is a deficient number, since it is larger than the sum of its proper divisors (488986737).

1318910991 is a wasteful number, since it uses less digits than its factorization.

1318910991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12022.

The product of its (nonzero) digits is 17496, while the sum is 42.

The square root of 1318910991 is about 36316.8141636901. The cubic root of 1318910991 is about 1096.6595606359.

The spelling of 1318910991 in words is "one billion, three hundred eighteen million, nine hundred ten thousand, nine hundred ninety-one".