645430887 has 24 divisors (see below), whose sum is σ = 947554608. Its totient is φ = 423273600.

The previous prime is 645430879. The next prime is 645430909. The reversal of 645430887 is 788034546.

It is not a de Polignac number, because 645430887 - 2³ = 645430879 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645430847) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 301812 + ... + 303942.

It is an arithmetic number, because the mean of its divisors is an integer number (39481442).

Almost surely, 2^645430887 is an apocalyptic number.

645430887 is a deficient number, since it is larger than the sum of its proper divisors (302123721).

645430887 is a wasteful number, since it uses less digits than its factorization.

645430887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2671 (or 2668 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The square root of 645430887 is about 25405.3318616388. The cubic root of 645430887 is about 864.2046157294.

The spelling of 645430887 in words is "six hundred forty-five million, four hundred thirty thousand, eight hundred eighty-seven".