667776665 has 8 divisors (see below), whose sum is σ = 802217088. Its totient is φ = 533631280.

The previous prime is 667776661. The next prime is 667776671. The reversal of 667776665 is 566677766.

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

It is not a de Polignac number, because 667776665 - 2² = 667776661 is a prime.

It is a super-3 number, since 3×667776665³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 667776665.

It is not an unprimeable number, because it can be changed into a prime (667776661) 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, 68747 + ... + 77856.

It is an arithmetic number, because the mean of its divisors is an integer number (100277136).

Almost surely, 2^667776665 is an apocalyptic number.

It is an amenable number.

667776665 is a deficient number, since it is larger than the sum of its proper divisors (134440423).

667776665 is a wasteful number, since it uses less digits than its factorization.

667776665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147519.

The product of its digits is 13335840, while the sum is 56.

The square root of 667776665 is about 25841.3750601627. The cubic root of 667776665 is about 874.0650323311.

The spelling of 667776665 in words is "six hundred sixty-seven million, seven hundred seventy-six thousand, six hundred sixty-five".