1989957440 has 224 divisors, whose sum is σ = 5272210944. Its totient is φ = 712212480.

The previous prime is 1989957391. The next prime is 1989957461. The reversal of 1989957440 is 447599891.

It is a super-2 number, since 2×1989957440² = 7919861226022707200, 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 31 ways as a sum of consecutive naturals, for example, 10994150 + ... + 10994330.

It is an arithmetic number, because the mean of its divisors is an integer number (23536656).

Almost surely, 2^1989957440 is an apocalyptic number.

1989957440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1989957440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2636105472).

1989957440 is an abundant number, since it is smaller than the sum of its proper divisors (3282253504).

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

1989957440 is a wasteful number, since it uses less digits than its factorization.

1989957440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305 (or 295 counting only the distinct ones).

The product of its (nonzero) digits is 3265920, while the sum is 56.

The square root of 1989957440 is about 44608.9390145069. The cubic root of 1989957440 is about 1257.8087049248.

The spelling of 1989957440 in words is "one billion, nine hundred eighty-nine million, nine hundred fifty-seven thousand, four hundred forty".