266277515138 has 4 divisors (see below), whose sum is σ = 399416272710. Its totient is φ = 133138757568.

The previous prime is 266277515137. The next prime is 266277515143. The reversal of 266277515138 is 831515772662.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 140637750289 + 125639764849 = 375017^2 + 354457^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 266277515138.

It is not an unprimeable number, because it can be changed into a prime (266277515137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66569378783 + ... + 66569378786.

Almost surely, 2^266277515138 is an apocalyptic number.

266277515138 is a deficient number, since it is larger than the sum of its proper divisors (133138757572).

266277515138 is a wasteful number, since it uses less digits than its factorization.

266277515138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133138757571.

The product of its digits is 4233600, while the sum is 53.

The spelling of 266277515138 in words is "two hundred sixty-six billion, two hundred seventy-seven million, five hundred fifteen thousand, one hundred thirty-eight".