645041042 has 8 divisors (see below), whose sum is σ = 970653756. Its totient is φ = 321489792.

The previous prime is 645041009. The next prime is 645041071. The reversal of 645041042 is 240140546.

It can be written as a sum of positive squares in 2 ways, for example, as 609053041 + 35988001 = 24679^2 + 5999^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 514583 + ... + 515834.

Almost surely, 2^645041042 is an apocalyptic number.

645041042 is a deficient number, since it is larger than the sum of its proper divisors (325612714).

645041042 is a wasteful number, since it uses less digits than its factorization.

645041042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1030732.

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 645041042 is about 25397.6581991332. The cubic root of 645041042 is about 864.0305853727.

Adding to 645041042 its reverse (240140546), we get a palindrome (885181588).

The spelling of 645041042 in words is "six hundred forty-five million, forty-one thousand, forty-two".