1137991 has 2 divisors, whose sum is σ = 1137992. Its totient is φ = 1137990.

The previous prime is 1137977. The next prime is 1138019. The reversal of 1137991 is 1997311.

It is a weak prime.

It is an emirp because it is prime and its reverse (1997311) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1137991 - 2⁵ = 1137959 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1137911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 568995 + 568996.

It is an arithmetic number, because the mean of its divisors is an integer number (568996).

2^1137991 is an apocalyptic number.

1137991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1137991 is an equidigital number, since it uses as much as digits as its factorization.

1137991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1701, while the sum is 31.

The square root of 1137991 is about 1066.7666099012. The cubic root of 1137991 is about 104.4029914049.

The spelling of 1137991 in words is "one million, one hundred thirty-seven thousand, nine hundred ninety-one".