1645764743 has 16 divisors (see below), whose sum is σ = 1991339520. Its totient is φ = 1328666976.

The previous prime is 1645764727. The next prime is 1645764767. The reversal of 1645764743 is 3474675461.

It is not a de Polignac number, because 1645764743 - 2⁴ = 1645764727 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645764443) 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 15 ways as a sum of consecutive naturals, for example, 12755 + ... + 58772.

It is an arithmetic number, because the mean of its divisors is an integer number (124458720).

Almost surely, 2^1645764743 is an apocalyptic number.

1645764743 is a deficient number, since it is larger than the sum of its proper divisors (345574777).

1645764743 is a wasteful number, since it uses less digits than its factorization.

1645764743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71726.

The product of its digits is 1693440, while the sum is 47.

The square root of 1645764743 is about 40568.0261166353. The cubic root of 1645764743 is about 1180.6538421279.

The spelling of 1645764743 in words is "one billion, six hundred forty-five million, seven hundred sixty-four thousand, seven hundred forty-three".