981111001 has 4 divisors (see below), whose sum is σ = 1056581092. Its totient is φ = 905640912.

The previous prime is 981110989. The next prime is 981111011. The reversal of 981111001 is 100111189.

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

It can be written as a sum of positive squares in 2 ways, for example, as 422261401 + 558849600 = 20549^2 + 23640^2 .

It is a cyclic number.

It is not a de Polignac number, because 981111001 - 2⁵ = 981110969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981111011) 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, 37735026 + ... + 37735051.

It is an arithmetic number, because the mean of its divisors is an integer number (264145273).

Almost surely, 2^981111001 is an apocalyptic number.

It is an amenable number.

981111001 is a deficient number, since it is larger than the sum of its proper divisors (75470091).

981111001 is a wasteful number, since it uses less digits than its factorization.

981111001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75470090.

The product of its (nonzero) digits is 72, while the sum is 22.

The square root of 981111001 is about 31322.6914712002. The cubic root of 981111001 is about 993.6636018606.

The spelling of 981111001 in words is "nine hundred eighty-one million, one hundred eleven thousand, one".