1668499761 has 16 divisors (see below), whose sum is σ = 2235212928. Its totient is φ = 1107072000.

The previous prime is 1668499747. The next prime is 1668499783. The reversal of 1668499761 is 1679948661.

It is not a de Polignac number, because 1668499761 - 2⁹ = 1668499249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1668499661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1041361 + ... + 1042961.

It is an arithmetic number, because the mean of its divisors is an integer number (139700808).

Almost surely, 2^1668499761 is an apocalyptic number.

It is an amenable number.

1668499761 is a deficient number, since it is larger than the sum of its proper divisors (566713167).

1668499761 is a wasteful number, since it uses less digits than its factorization.

1668499761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3032.

The product of its digits is 3919104, while the sum is 57.

The square root of 1668499761 is about 40847.2736054685. The cubic root of 1668499761 is about 1186.0656169647.

The spelling of 1668499761 in words is "one billion, six hundred sixty-eight million, four hundred ninety-nine thousand, seven hundred sixty-one".