266642661 has 8 divisors (see below), whose sum is σ = 357118720. Its totient is φ = 176964192.

The previous prime is 266642633. The next prime is 266642669. The reversal of 266642661 is 166246662.

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

It is not a de Polignac number, because 266642661 - 2⁷ = 266642533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266642669) 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, 198616 + ... + 199953.

It is an arithmetic number, because the mean of its divisors is an integer number (44639840).

Almost surely, 2^266642661 is an apocalyptic number.

It is an amenable number.

266642661 is a deficient number, since it is larger than the sum of its proper divisors (90476059).

266642661 is a wasteful number, since it uses less digits than its factorization.

266642661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398795.

The product of its digits is 124416, while the sum is 39.

The square root of 266642661 is about 16329.1965815836. The cubic root of 266642661 is about 643.6402748105.

The spelling of 266642661 in words is "two hundred sixty-six million, six hundred forty-two thousand, six hundred sixty-one".