981388433 has 4 divisors (see below), whose sum is σ = 982508340. Its totient is φ = 980268528.

The previous prime is 981388409. The next prime is 981388453. The reversal of 981388433 is 334883189.

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 764356609 + 217031824 = 27647^2 + 14732^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-981388433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981388453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 558638 + ... + 560391.

It is an arithmetic number, because the mean of its divisors is an integer number (245627085).

Almost surely, 2^981388433 is an apocalyptic number.

It is an amenable number.

981388433 is a deficient number, since it is larger than the sum of its proper divisors (1119907).

981388433 is a wasteful number, since it uses less digits than its factorization.

981388433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1119906.

The product of its digits is 497664, while the sum is 47.

The square root of 981388433 is about 31327.1197686605. The cubic root of 981388433 is about 993.7572535473.

The spelling of 981388433 in words is "nine hundred eighty-one million, three hundred eighty-eight thousand, four hundred thirty-three".