1643253775 has 12 divisors (see below), whose sum is σ = 2040977752. Its totient is φ = 1312446240.

The previous prime is 1643253769. The next prime is 1643253823. The reversal of 1643253775 is 5773523461.

It is not a de Polignac number, because 1643253775 - 2⁵ = 1643253743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38289 + ... + 68938.

Almost surely, 2^1643253775 is an apocalyptic number.

1643253775 is a deficient number, since it is larger than the sum of its proper divisors (397723977).

1643253775 is a wasteful number, since it uses less digits than its factorization.

1643253775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107850 (or 107845 counting only the distinct ones).

The product of its digits is 529200, while the sum is 43.

The square root of 1643253775 is about 40537.0666797685. The cubic root of 1643253775 is about 1180.0530893954.

It can be divided in two parts, 164325 and 3775, that added together give a square (168100 = 410²).

The spelling of 1643253775 in words is "one billion, six hundred forty-three million, two hundred fifty-three thousand, seven hundred seventy-five".