1391119987 has 2 divisors, whose sum is σ = 1391119988.
Its totient is φ = 1391119986.
The previous prime is 1391119981. The next prime is 1391119993. The reversal of 1391119987 is 7899111931.
It is a balanced prime because it is at equal distance from previous prime (1391119981) and next prime (1391119993).
It is a cyclic number.
It is not a de Polignac number, because 1391119987 - 27 = 1391119859 is a prime.
It is a self number, because there is not a number n which added to its sum of digits gives 1391119987.
It is not a weakly prime, because it can be changed into another prime (1391119981) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695559993 + 695559994.
It is an arithmetic number, because the mean of its divisors is an integer number (695559994).
Almost surely, 21391119987 is an apocalyptic number.
1391119987 is a deficient number, since it is larger than the sum of its proper divisors (1).
1391119987 is an equidigital number, since it uses as much as digits as its factorization.
1391119987 is an evil number, because the sum of its binary digits is even.
The product of its digits is 122472, while the sum is 49.
The square root of 1391119987 is about 37297.7209357355.
The cubic root of 1391119987 is about 1116.3186920906.
The spelling of 1391119987 in words is "one billion, three hundred ninety-one million, one hundred nineteen thousand, nine hundred eighty-seven".