668887081 has 4 divisors (see below), whose sum is σ = 697969152. Its totient is φ = 639805012.

The previous prime is 668887069. The next prime is 668887103. The reversal of 668887081 is 180788866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668887081 is a prime.

It is a super-2 number, since 2×668887081² = 894819854257401122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668887481) 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, 14541001 + ... + 14541046.

It is an arithmetic number, because the mean of its divisors is an integer number (174492288).

Almost surely, 2^668887081 is an apocalyptic number.

It is an amenable number.

668887081 is a deficient number, since it is larger than the sum of its proper divisors (29082071).

668887081 is a wasteful number, since it uses less digits than its factorization.

668887081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29082070.

The product of its (nonzero) digits is 1032192, while the sum is 52.

The square root of 668887081 is about 25862.8513702569. The cubic root of 668887081 is about 874.5492452765.

The spelling of 668887081 in words is "six hundred sixty-eight million, eight hundred eighty-seven thousand, eighty-one".