1666240402263 has 24 divisors (see below), whose sum is σ = 2446682318208. Its totient is φ = 1006607459088.

The previous prime is 1666240402261. The next prime is 1666240402279. The reversal of 1666240402263 is 3622040426661.

It is not a de Polignac number, because 1666240402263 - 2¹ = 1666240402261 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666240402261) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33421645 + ... + 33471462.

It is an arithmetic number, because the mean of its divisors is an integer number (101945096592).

Almost surely, 2^{1666240402263} is an apocalyptic number.

1666240402263 is a deficient number, since it is larger than the sum of its proper divisors (780441915945).

1666240402263 is a wasteful number, since it uses less digits than its factorization.

1666240402263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66893171 (or 66893152 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 42.

The spelling of 1666240402263 in words is "one trillion, six hundred sixty-six billion, two hundred forty million, four hundred two thousand, two hundred sixty-three".