1989943280 has 40 divisors (see below), whose sum is σ = 4982514432. Its totient is φ = 734747904.

The previous prime is 1989943273. The next prime is 1989943297. The reversal of 1989943280 is 823499891.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 955664 + ... + 957743.

Almost surely, 2^1989943280 is an apocalyptic number.

1989943280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1989943280 is an abundant number, since it is smaller than the sum of its proper divisors (2992571152).

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

1989943280 is a wasteful number, since it uses less digits than its factorization.

1989943280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1913433 (or 1913427 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 53.

The square root of 1989943280 is about 44608.7803016402. The cubic root of 1989943280 is about 1257.8057215087.

The spelling of 1989943280 in words is "one billion, nine hundred eighty-nine million, nine hundred forty-three thousand, two hundred eighty".