645888006 has 80 divisors (see below), whose sum is σ = 1514842560. Its totient is φ = 205476480.

The previous prime is 645887951. The next prime is 645888011. The reversal of 645888006 is 600888546.

645888006 is a `hidden beast` number, since 64 + 588 + 8 + 0 + 0 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 311140 + ... + 313208.

It is an arithmetic number, because the mean of its divisors is an integer number (18935532).

Almost surely, 2^645888006 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645888006, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (757421280).

645888006 is an abundant number, since it is smaller than the sum of its proper divisors (868954554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645888006 is a wasteful number, since it uses less digits than its factorization.

645888006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2171 (or 2162 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The square root of 645888006 is about 25414.3267862834. The cubic root of 645888006 is about 864.4085885753.

The spelling of 645888006 in words is "six hundred forty-five million, eight hundred eighty-eight thousand, six".