266697433987 has 4 divisors (see below), whose sum is σ = 266698614096. Its totient is φ = 266696253880.

The previous prime is 266697433963. The next prime is 266697433993. The reversal of 266697433987 is 789334796662.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 789334796662 = 2 ⋅394667398331.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-266697433987 is a prime.

It is a super-2 number, since 2×266697433987² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 2.

It is not an unprimeable number, because it can be changed into a prime (266697433907) 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, 133108 + ... + 742369.

It is an arithmetic number, because the mean of its divisors is an integer number (66674653524).

Almost surely, 2^266697433987 is an apocalyptic number.

266697433987 is a deficient number, since it is larger than the sum of its proper divisors (1180109).

266697433987 is an equidigital number, since it uses as much as digits as its factorization.

266697433987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1180108.

The product of its digits is 493807104, while the sum is 70.

The spelling of 266697433987 in words is "two hundred sixty-six billion, six hundred ninety-seven million, four hundred thirty-three thousand, nine hundred eighty-seven".