667777745 has 32 divisors (see below), whose sum is σ = 866460672. Its totient is φ = 492795072.

The previous prime is 667777717. The next prime is 667777807. The reversal of 667777745 is 547777766.

It is a cyclic number.

It is not a de Polignac number, because 667777745 - 2¹⁴ = 667761361 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 409622 + ... + 411248.

It is an arithmetic number, because the mean of its divisors is an integer number (27076896).

Almost surely, 2^667777745 is an apocalyptic number.

It is an amenable number.

667777745 is a deficient number, since it is larger than the sum of its proper divisors (198682927).

667777745 is a wasteful number, since it uses less digits than its factorization.

667777745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1781.

The product of its digits is 12101040, while the sum is 56.

The square root of 667777745 is about 25841.3959568751. The cubic root of 667777745 is about 874.0655035414.

The spelling of 667777745 in words is "six hundred sixty-seven million, seven hundred seventy-seven thousand, seven hundred forty-five".