981035991 has 12 divisors (see below), whose sum is σ = 1526056168. Its totient is φ = 603714384.

The previous prime is 981035953. The next prime is 981036037. The reversal of 981035991 is 199530189.

It is not a de Polignac number, because 981035991 - 2⁹ = 981035479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981035941) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4192345 + ... + 4192578.

Almost surely, 2^981035991 is an apocalyptic number.

981035991 is a deficient number, since it is larger than the sum of its proper divisors (545020177).

981035991 is a wasteful number, since it uses less digits than its factorization.

981035991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8384942 (or 8384939 counting only the distinct ones).

The product of its (nonzero) digits is 87480, while the sum is 45.

The square root of 981035991 is about 31321.4940735591. The cubic root of 981035991 is about 993.6382779825.

The spelling of 981035991 in words is "nine hundred eighty-one million, thirty-five thousand, nine hundred ninety-one".