645442143 has 8 divisors (see below), whose sum is σ = 861511728. Its totient is φ = 429833664.

The previous prime is 645442099. The next prime is 645442153. The reversal of 645442143 is 341244546.

It is a happy number.

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

It is not a de Polignac number, because 645442143 - 2⁶ = 645442079 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645442153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111996 + ... + 117617.

It is an arithmetic number, because the mean of its divisors is an integer number (107688966).

Almost surely, 2^645442143 is an apocalyptic number.

645442143 is a deficient number, since it is larger than the sum of its proper divisors (216069585).

645442143 is a wasteful number, since it uses less digits than its factorization.

645442143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230553.

The product of its digits is 46080, while the sum is 33.

The square root of 645442143 is about 25405.5533889738. The cubic root of 645442143 is about 864.2096394693.

Adding to 645442143 its reverse (341244546), we get a palindrome (986686689).

The spelling of 645442143 in words is "six hundred forty-five million, four hundred forty-two thousand, one hundred forty-three".