6539898981 has 16 divisors (see below), whose sum is σ = 10871520768. Its totient is φ = 3397350000.

The previous prime is 6539898947. The next prime is 6539899007. The reversal of 6539898981 is 1898989356.

It is not a de Polignac number, because 6539898981 - 2⁶ = 6539898917 is a prime.

It is a super-2 number, since 2×6539898981² = 85540557363369676722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6539898901) 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 15 ways as a sum of consecutive naturals, for example, 14155395 + ... + 14155856.

It is an arithmetic number, because the mean of its divisors is an integer number (679470048).

Almost surely, 2^6539898981 is an apocalyptic number.

It is an amenable number.

6539898981 is a deficient number, since it is larger than the sum of its proper divisors (4331621787).

6539898981 is a wasteful number, since it uses less digits than its factorization.

6539898981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28311272.

The product of its digits is 33592320, while the sum is 66.

The square root of 6539898981 is about 80869.6418997883. The cubic root of 6539898981 is about 1870.0663403119.

The spelling of 6539898981 in words is "six billion, five hundred thirty-nine million, eight hundred ninety-eight thousand, nine hundred eighty-one".