645111555999 has 8 divisors (see below), whose sum is σ = 867760677552. Its totient is φ = 426268402560.

The previous prime is 645111555931. The next prime is 645111556021. The reversal of 645111555999 is 999555111546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 645111555999 - 2⁷ = 645111555871 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645111655999) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 951491632 + ... + 951492309.

It is an arithmetic number, because the mean of its divisors is an integer number (108470084694).

Almost surely, 2^645111555999 is an apocalyptic number.

645111555999 is a deficient number, since it is larger than the sum of its proper divisors (222649121553).

645111555999 is a wasteful number, since it uses less digits than its factorization.

645111555999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1902984057.

The product of its digits is 10935000, while the sum is 60.

The spelling of 645111555999 in words is "six hundred forty-five billion, one hundred eleven million, five hundred fifty-five thousand, nine hundred ninety-nine".