1645643242 has 8 divisors (see below), whose sum is σ = 2520985536. Its totient is φ = 805314732.

The previous prime is 1645643171. The next prime is 1645643291. The reversal of 1645643242 is 2423465461.

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, 8753328 + ... + 8753515.

It is an arithmetic number, because the mean of its divisors is an integer number (315123192).

Almost surely, 2^1645643242 is an apocalyptic number.

1645643242 is a deficient number, since it is larger than the sum of its proper divisors (875342294).

1645643242 is a wasteful number, since it uses less digits than its factorization.

1645643242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17506892.

The product of its digits is 138240, while the sum is 37.

The square root of 1645643242 is about 40566.5285919316. The cubic root of 1645643242 is about 1180.6247869114.

The spelling of 1645643242 in words is "one billion, six hundred forty-five million, six hundred forty-three thousand, two hundred forty-two".