266984561 has 4 divisors (see below), whose sum is σ = 281036400. Its totient is φ = 252932724.

The previous prime is 266984537. The next prime is 266984591. The reversal of 266984561 is 165489662.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-266984561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (266984521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7025891 + ... + 7025928.

It is an arithmetic number, because the mean of its divisors is an integer number (70259100).

Almost surely, 2^266984561 is an apocalyptic number.

It is an amenable number.

266984561 is a deficient number, since it is larger than the sum of its proper divisors (14051839).

266984561 is a wasteful number, since it uses less digits than its factorization.

266984561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14051838.

The product of its digits is 622080, while the sum is 47.

The square root of 266984561 is about 16339.6622058107. The cubic root of 266984561 is about 643.9152578399.

The spelling of 266984561 in words is "two hundred sixty-six million, nine hundred eighty-four thousand, five hundred sixty-one".