668387732 has 6 divisors (see below), whose sum is σ = 1169678538. Its totient is φ = 334193864.

The previous prime is 668387723. The next prime is 668387767. The reversal of 668387732 is 237783866.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 618317956 + 50069776 = 24866^2 + 7076^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83548463 + ... + 83548470.

It is an arithmetic number, because the mean of its divisors is an integer number (194946423).

Almost surely, 2^668387732 is an apocalyptic number.

It is an amenable number.

668387732 is a deficient number, since it is larger than the sum of its proper divisors (501290806).

668387732 is a wasteful number, since it uses less digits than its factorization.

668387732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167096937 (or 167096935 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 50.

The square root of 668387732 is about 25853.1957792456. The cubic root of 668387732 is about 874.3315632886.

The spelling of 668387732 in words is "six hundred sixty-eight million, three hundred eighty-seven thousand, seven hundred thirty-two".