1081983991 has 8 divisors (see below), whose sum is σ = 1180589184. Its totient is φ = 983419320.

The previous prime is 1081983983. The next prime is 1081984019. The reversal of 1081983991 is 1993891801.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1081983991 - 2³ = 1081983983 is a prime.

It is a super-3 number, since 3×1081983991³ (a number of 28 digits) contains 333 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 (1081983911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82876 + ... + 95038.

It is an arithmetic number, because the mean of its divisors is an integer number (147573648).

Almost surely, 2^1081983991 is an apocalyptic number.

1081983991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1081983991 is a deficient number, since it is larger than the sum of its proper divisors (98605193).

1081983991 is a wasteful number, since it uses less digits than its factorization.

1081983991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20261.

The product of its (nonzero) digits is 139968, while the sum is 49.

The square root of 1081983991 is about 32893.5250619328. The cubic root of 1081983991 is about 1026.6134386700.

The spelling of 1081983991 in words is "one billion, eighty-one million, nine hundred eighty-three thousand, nine hundred ninety-one".