266640752401 has 4 divisors (see below), whose sum is σ = 266722572400. Its totient is φ = 266558932404.

The previous prime is 266640752369. The next prime is 266640752419. The reversal of 266640752401 is 104257046662.

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 not a de Polignac number, because 266640752401 - 2⁵ = 266640752369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (266640752491) 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, 40905111 + ... + 40911628.

It is an arithmetic number, because the mean of its divisors is an integer number (66680643100).

Almost surely, 2^266640752401 is an apocalyptic number.

It is an amenable number.

266640752401 is a deficient number, since it is larger than the sum of its proper divisors (81819999).

266640752401 is an equidigital number, since it uses as much as digits as its factorization.

266640752401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81819998.

The product of its (nonzero) digits is 483840, while the sum is 43.

The spelling of 266640752401 in words is "two hundred sixty-six billion, six hundred forty million, seven hundred fifty-two thousand, four hundred one".