666261662037403 has 4 divisors (see below), whose sum is σ = 680437442080800. Its totient is φ = 652085881994008.

The previous prime is 666261662037401. The next prime is 666261662037407. The reversal of 666261662037403 is 304730266162666.

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

It is a cyclic number.

It is not a de Polignac number, because 666261662037403 - 2¹ = 666261662037401 is a prime.

It is a super-2 number, since 2×666261662037403² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666261662037401) 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, 7087890021628 + ... + 7087890021721.

It is an arithmetic number, because the mean of its divisors is an integer number (170109360520200).

Almost surely, 2^{666261662037403} is an apocalyptic number.

666261662037403 is a deficient number, since it is larger than the sum of its proper divisors (14175780043397).

666261662037403 is a wasteful number, since it uses less digits than its factorization.

666261662037403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14175780043396.

The product of its (nonzero) digits is 47029248, while the sum is 58.

The spelling of 666261662037403 in words is "six hundred sixty-six trillion, two hundred sixty-one billion, six hundred sixty-two million, thirty-seven thousand, four hundred three".