668140081539 has 8 divisors (see below), whose sum is σ = 1018118219520. Its totient is φ = 381794332296.

The previous prime is 668140081537. The next prime is 668140081559. The reversal of 668140081539 is 935180041866.

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

It is not a de Polignac number, because 668140081539 - 2¹ = 668140081537 is a prime.

It is a super-2 number, since 2×668140081539² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 668140081491 and 668140081500.

It is not an unprimeable number, because it can be changed into a prime (668140081537) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15908097159 + ... + 15908097200.

It is an arithmetic number, because the mean of its divisors is an integer number (127264777440).

Almost surely, 2^668140081539 is an apocalyptic number.

668140081539 is a deficient number, since it is larger than the sum of its proper divisors (349978137981).

668140081539 is a wasteful number, since it uses less digits than its factorization.

668140081539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31816194369.

The product of its (nonzero) digits is 1244160, while the sum is 51.

The spelling of 668140081539 in words is "six hundred sixty-eight billion, one hundred forty million, eighty-one thousand, five hundred thirty-nine".