645170103 has 28 divisors (see below), whose sum is σ = 970164288. Its totient is φ = 428846400.

The previous prime is 645170087. The next prime is 645170107. The reversal of 645170103 is 301071546.

645170103 is a `hidden beast` number, since 645 + 1 + 7 + 0 + 10 + 3 = 666.

It is not a de Polignac number, because 645170103 - 2⁴ = 645170087 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645170107) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 291226 + ... + 293432.

Almost surely, 2^645170103 is an apocalyptic number.

645170103 is a deficient number, since it is larger than the sum of its proper divisors (324994185).

645170103 is an equidigital number, since it uses as much as digits as its factorization.

645170103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2626 (or 2611 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 645170103 is about 25400.1988771742. The cubic root of 645170103 is about 864.0882071403.

The spelling of 645170103 in words is "six hundred forty-five million, one hundred seventy thousand, one hundred three".