6637231981 has 8 divisors (see below), whose sum is σ = 6989450400. Its totient is φ = 6285302640.

The previous prime is 6637231973. The next prime is 6637231999. The reversal of 6637231981 is 1891327366.

6637231981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6637231981 - 2³ = 6637231973 is a prime.

It is a super-2 number, since 2×6637231981² = 88105696739218368722, 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 (6637231961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24310 + ... + 117751.

It is an arithmetic number, because the mean of its divisors is an integer number (873681300).

Almost surely, 2^6637231981 is an apocalyptic number.

It is an amenable number.

6637231981 is a deficient number, since it is larger than the sum of its proper divisors (352218419).

6637231981 is a wasteful number, since it uses less digits than its factorization.

6637231981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144539.

The product of its digits is 326592, while the sum is 46.

The square root of 6637231981 is about 81469.2087908064. The cubic root of 6637231981 is about 1879.2980611906.

The spelling of 6637231981 in words is "six billion, six hundred thirty-seven million, two hundred thirty-one thousand, nine hundred eighty-one".