1077991 has 4 divisors (see below), whose sum is σ = 1092832. Its totient is φ = 1063152.

The previous prime is 1077977. The next prime is 1077997. The reversal of 1077991 is 1997701.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1077991 - 2⁷ = 1077863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1077997) 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 in 3 ways as a sum of consecutive naturals, for example, 7311 + ... + 7456.

It is an arithmetic number, because the mean of its divisors is an integer number (273208).

2^1077991 is an apocalyptic number.

1077991 is a deficient number, since it is larger than the sum of its proper divisors (14841).

1077991 is an equidigital number, since it uses as much as digits as its factorization.

1077991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14840.

The product of its (nonzero) digits is 3969, while the sum is 34.

The square root of 1077991 is about 1038.2634540424. The cubic root of 1077991 is about 102.5348998746.

The spelling of 1077991 in words is "one million, seventy-seven thousand, nine hundred ninety-one".