1988797440 has 352 divisors, whose sum is σ = 7428153600. Its totient is φ = 444727296.

The previous prime is 1988797403. The next prime is 1988797463. The reversal of 1988797440 is 447978891.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5698386 + ... + 5698734.

Almost surely, 2^1988797440 is an apocalyptic number.

1988797440 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 1988797440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3714076800).

1988797440 is an abundant number, since it is smaller than the sum of its proper divisors (5439356160).

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

1988797440 is a wasteful number, since it uses less digits than its factorization.

1988797440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437 (or 419 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 57.

The square root of 1988797440 is about 44595.9352407818. The cubic root of 1988797440 is about 1257.5642538513.

The spelling of 1988797440 in words is "one billion, nine hundred eighty-eight million, seven hundred ninety-seven thousand, four hundred forty".