1989645442 has 8 divisors (see below), whose sum is σ = 2985062796. Its totient is φ = 994624512.

The previous prime is 1989645409. The next prime is 1989645481. The reversal of 1989645442 is 2445469891.

It can be written as a sum of positive squares in 2 ways, for example, as 1988178921 + 1466521 = 44589^2 + 1211^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 1989645442.

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, 86223 + ... + 106834.

Almost surely, 2^1989645442 is an apocalyptic number.

1989645442 is a deficient number, since it is larger than the sum of its proper divisors (995417354).

1989645442 is a wasteful number, since it uses less digits than its factorization.

1989645442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198212.

The product of its digits is 2488320, while the sum is 52.

The square root of 1989645442 is about 44605.4418428963. The cubic root of 1989645442 is about 1257.7429657782.

The spelling of 1989645442 in words is "one billion, nine hundred eighty-nine million, six hundred forty-five thousand, four hundred forty-two".