1989774144 has 42 divisors (see below), whose sum is σ = 5703329970. Its totient is φ = 663257856.

The previous prime is 1989774133. The next prime is 1989774167. The reversal of 1989774144 is 4414779891.

It can be written as a sum of positive squares in only one way, i.e., 1592967744 + 396806400 = 39912^2 + 19920^2 .

It is a super-2 number, since 2×1989774144² = 7918402288261865472, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1726659 + ... + 1727810.

Almost surely, 2^1989774144 is an apocalyptic number.

It is an amenable number.

1989774144 is an abundant number, since it is smaller than the sum of its proper divisors (3713555826).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1989774144 is a wasteful number, since it uses less digits than its factorization.

1989774144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3454487 (or 3454474 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 54.

The square root of 1989774144 is about 44606.8844910738. The cubic root of 1989774144 is about 1257.7700846041.

The spelling of 1989774144 in words is "one billion, nine hundred eighty-nine million, seven hundred seventy-four thousand, one hundred forty-four".