6389981 has 4 divisors (see below), whose sum is σ = 6881532. Its totient is φ = 5898432.

The previous prime is 6389963. The next prime is 6389983. The reversal of 6389981 is 1899836.

6389981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 1836025 + 4553956 = 1355^2 + 2134^2 .

It is a cyclic number.

It is not a de Polignac number, because 6389981 - 2⁶ = 6389917 is a prime.

It is a super-2 number, since 2×6389981² = 81663714360722, 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 (6389983) 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, 245756 + ... + 245781.

It is an arithmetic number, because the mean of its divisors is an integer number (1720383).

Almost surely, 2^6389981 is an apocalyptic number.

It is an amenable number.

6389981 is a deficient number, since it is larger than the sum of its proper divisors (491551).

6389981 is a wasteful number, since it uses less digits than its factorization.

6389981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491550.

The product of its digits is 93312, while the sum is 44.

The square root of 6389981 is about 2527.8411738082. The cubic root of 6389981 is about 185.5666192475.

The spelling of 6389981 in words is "six million, three hundred eighty-nine thousand, nine hundred eighty-one".