266947381 has 2 divisors, whose sum is σ = 266947382. Its totient is φ = 266947380.

The previous prime is 266947337. The next prime is 266947409. The reversal of 266947381 is 183749662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 203490225 + 63457156 = 14265^2 + 7966^2 .

It is a cyclic number.

It is not a de Polignac number, because 266947381 - 2¹⁹ = 266423093 is a prime.

It is a super-2 number, since 2×266947381² = 142521808445518322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (266947301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133473690 + 133473691.

It is an arithmetic number, because the mean of its divisors is an integer number (133473691).

Almost surely, 2^266947381 is an apocalyptic number.

It is an amenable number.

266947381 is a deficient number, since it is larger than the sum of its proper divisors (1).

266947381 is an equidigital number, since it uses as much as digits as its factorization.

266947381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 46.

The square root of 266947381 is about 16338.5244437801. The cubic root of 266947381 is about 643.8853661231.

The spelling of 266947381 in words is "two hundred sixty-six million, nine hundred forty-seven thousand, three hundred eighty-one".