668481767 has 4 divisors (see below), whose sum is σ = 668678376. Its totient is φ = 668285160.

The previous prime is 668481763. The next prime is 668481787. The reversal of 668481767 is 767184866.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 668481767 - 2² = 668481763 is a prime.

It is a super-2 number, since 2×668481767² = 893735745622884578, 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 (668481761) 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 3 ways as a sum of consecutive naturals, for example, 93113 + ... + 100034.

It is an arithmetic number, because the mean of its divisors is an integer number (167169594).

Almost surely, 2^668481767 is an apocalyptic number.

668481767 is a deficient number, since it is larger than the sum of its proper divisors (196609).

668481767 is a wasteful number, since it uses less digits than its factorization.

668481767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196608.

The product of its digits is 2709504, while the sum is 53.

The square root of 668481767 is about 25855.0143492515. The cubic root of 668481767 is about 874.3725643968.

The spelling of 668481767 in words is "six hundred sixty-eight million, four hundred eighty-one thousand, seven hundred sixty-seven".