166651516503 has 16 divisors (see below), whose sum is σ = 246905330400. Its totient is φ = 111094623360.

The previous prime is 166651516463. The next prime is 166651516519. The reversal of 166651516503 is 305615156661.

It is not a de Polignac number, because 166651516503 - 2²⁰ = 166650467927 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166651516583) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 326943 + ... + 663471.

It is an arithmetic number, because the mean of its divisors is an integer number (15431583150).

Almost surely, 2^166651516503 is an apocalyptic number.

166651516503 is a deficient number, since it is larger than the sum of its proper divisors (80253813897).

166651516503 is a wasteful number, since it uses less digits than its factorization.

166651516503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354879 (or 354873 counting only the distinct ones).

The product of its (nonzero) digits is 486000, while the sum is 45.

The spelling of 166651516503 in words is "one hundred sixty-six billion, six hundred fifty-one million, five hundred sixteen thousand, five hundred three".