645335552 has 40 divisors (see below), whose sum is σ = 1294446912. Its totient is φ = 321408000.

The previous prime is 645335533. The next prime is 645335557. The reversal of 645335552 is 255533546.

It is not an unprimeable number, because it can be changed into a prime (645335557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136427 + ... + 141077.

Almost surely, 2^645335552 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645335552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (647223456).

645335552 is an abundant number, since it is smaller than the sum of its proper divisors (649111360).

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

645335552 is an equidigital number, since it uses as much as digits as its factorization.

645335552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4940 (or 4924 counting only the distinct ones).

The product of its digits is 270000, while the sum is 38.

The square root of 645335552 is about 25403.4555129809. The cubic root of 645335552 is about 864.1620637921.

The spelling of 645335552 in words is "six hundred forty-five million, three hundred thirty-five thousand, five hundred fifty-two".