266983821 has 12 divisors (see below), whose sum is σ = 415308348. Its totient is φ = 164297664.

The previous prime is 266983817. The next prime is 266983883. The reversal of 266983821 is 128389662.

266983821 is a `hidden beast` number, since 266 + 9 + 8 + 382 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 29484900 + 237498921 = 5430^2 + 15411^2 .

It is not a de Polignac number, because 266983821 - 2² = 266983817 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266983121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1140840 + ... + 1141073.

It is an arithmetic number, because the mean of its divisors is an integer number (34609029).

Almost surely, 2^266983821 is an apocalyptic number.

It is an amenable number.

266983821 is a deficient number, since it is larger than the sum of its proper divisors (148324527).

266983821 is a wasteful number, since it uses less digits than its factorization.

266983821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2281932 (or 2281929 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 266983821 is about 16339.6395615081. The cubic root of 266983821 is about 643.9146629269.

The spelling of 266983821 in words is "two hundred sixty-six million, nine hundred eighty-three thousand, eight hundred twenty-one".