266401623 has 4 divisors (see below), whose sum is σ = 355202168. Its totient is φ = 177601080.

The previous prime is 266401621. The next prime is 266401649. The reversal of 266401623 is 326104662.

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

It is not a de Polignac number, because 266401623 - 2¹ = 266401621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266401621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44400268 + ... + 44400273.

It is an arithmetic number, because the mean of its divisors is an integer number (88800542).

Almost surely, 2^266401623 is an apocalyptic number.

266401623 is a deficient number, since it is larger than the sum of its proper divisors (88800545).

266401623 is an equidigital number, since it uses as much as digits as its factorization.

266401623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88800544.

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 266401623 is about 16321.8143292956. The cubic root of 266401623 is about 643.4462716760.

The spelling of 266401623 in words is "two hundred sixty-six million, four hundred one thousand, six hundred twenty-three".