1139981 has 4 divisors (see below), whose sum is σ = 1200000. Its totient is φ = 1079964.

The previous prime is 1139959. The next prime is 1139989. The reversal of 1139981 is 1899311.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1139981 - 2⁶ = 1139917 is a prime.

It is a super-2 number, since 2×1139981² = 2599113360722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1139989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29981 + ... + 30018.

It is an arithmetic number, because the mean of its divisors is an integer number (300000).

2^1139981 is an apocalyptic number.

It is an amenable number.

1139981 is a deficient number, since it is larger than the sum of its proper divisors (60019).

1139981 is an equidigital number, since it uses as much as digits as its factorization.

1139981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60018.

The product of its digits is 1944, while the sum is 32.

The square root of 1139981 is about 1067.6989276008. The cubic root of 1139981 is about 104.4638123213.

The spelling of 1139981 in words is "one million, one hundred thirty-nine thousand, nine hundred eighty-one".