266451661 has 16 divisors (see below), whose sum is σ = 318326400. Its totient is φ = 222804960.

The previous prime is 266451643. The next prime is 266451683. The reversal of 266451661 is 166154662.

It is not a de Polignac number, because 266451661 - 2¹⁹ = 265927373 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 266451661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266452661) 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, 4590 + ... + 23536.

It is an arithmetic number, because the mean of its divisors is an integer number (19895400).

Almost surely, 2^266451661 is an apocalyptic number.

It is an amenable number.

266451661 is a deficient number, since it is larger than the sum of its proper divisors (51874739).

266451661 is an equidigital number, since it uses as much as digits as its factorization.

266451661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19009 (or 18995 counting only the distinct ones).

The product of its digits is 51840, while the sum is 37.

The square root of 266451661 is about 16323.3471138734. The cubic root of 266451661 is about 643.4865551505.

The spelling of 266451661 in words is "two hundred sixty-six million, four hundred fifty-one thousand, six hundred sixty-one".