1987989696 has 448 divisors, whose sum is σ = 7428341760. Its totient is φ = 506373120.

The previous prime is 1987989671. The next prime is 1987989697. The reversal of 1987989696 is 6969897891.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (1987989697) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8914641 + ... + 8914863.

It is an arithmetic number, because the mean of its divisors is an integer number (16581120).

Almost surely, 2^1987989696 is an apocalyptic number.

1987989696 is a gapful number since it is divisible by the number (16) 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 1987989696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3714170880).

1987989696 is an abundant number, since it is smaller than the sum of its proper divisors (5440352064).

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

1987989696 is a wasteful number, since it uses less digits than its factorization.

1987989696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329 (or 313 counting only the distinct ones).

The product of its digits is 105815808, while the sum is 72.

The square root of 1987989696 is about 44586.8780696743. The cubic root of 1987989696 is about 1257.3939788380.

The spelling of 1987989696 in words is "one billion, nine hundred eighty-seven million, nine hundred eighty-nine thousand, six hundred ninety-six".