1990659888 has 330 divisors, whose sum is σ = 6886373604. Its totient is φ = 555532992.

The previous prime is 1990659883. The next prime is 1990659893. The reversal of 1990659888 is 8889560991.

It is an interprime number because it is at equal distance from previous prime (1990659883) and next prime (1990659893).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (1990659883) by changing a digit.

It is a polite number, since it can be written in 65 ways as a sum of consecutive naturals, for example, 46294395 + ... + 46294437.

Almost surely, 2^1990659888 is an apocalyptic number.

1990659888 is a gapful number since it is divisible by the number (18) 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 1990659888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3443186802).

1990659888 is an abundant number, since it is smaller than the sum of its proper divisors (4895713716).

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

1990659888 is an frugal number, since it uses more digits than its factorization.

1990659888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95 (or 55 counting only the distinct ones).

The product of its (nonzero) digits is 11197440, while the sum is 63.

The square root of 1990659888 is about 44616.8117193508. The cubic root of 1990659888 is about 1257.9566882014.

The spelling of 1990659888 in words is "one billion, nine hundred ninety million, six hundred fifty-nine thousand, eight hundred eighty-eight".