8001990 has 96 divisors (see below), whose sum is σ = 22407840. Its totient is φ = 2052864.

The previous prime is 8001971. The next prime is 8001991. The reversal of 8001990 is 991008.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8001991) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 89866 + ... + 89954.

It is an arithmetic number, because the mean of its divisors is an integer number (233415).

Almost surely, 2^8001990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8001990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11203920).

8001990 is an abundant number, since it is smaller than the sum of its proper divisors (14405850).

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

8001990 is a wasteful number, since it uses less digits than its factorization.

8001990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148 (or 136 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 27.

The square root of 8001990 is about 2828.7788884959. The cubic root of 8001990 is about 200.0165819585.

Adding to 8001990 its reverse (991008), we get a palindrome (8992998).

The spelling of 8001990 in words is "eight million, one thousand, nine hundred ninety".