645824442 has 16 divisors (see below), whose sum is σ = 1292614272. Its totient is φ = 215113920.

The previous prime is 645824437. The next prime is 645824453. The reversal of 645824442 is 244428546.

It is a super-2 number, since 2×645824442² = 834178419769222728, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 645824442.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31378 + ... + 47709.

It is an arithmetic number, because the mean of its divisors is an integer number (80788392).

Almost surely, 2^645824442 is an apocalyptic number.

645824442 is an abundant number, since it is smaller than the sum of its proper divisors (646789830).

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

645824442 is a wasteful number, since it uses less digits than its factorization.

645824442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80453.

The product of its digits is 245760, while the sum is 39.

The square root of 645824442 is about 25413.0762010426. The cubic root of 645824442 is about 864.3802311978.

The spelling of 645824442 in words is "six hundred forty-five million, eight hundred twenty-four thousand, four hundred forty-two".