1990646028 has 288 divisors, whose sum is σ = 6246309888. Its totient is φ = 522547200.

The previous prime is 1990646011. The next prime is 1990646033. The reversal of 1990646028 is 8206460991.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 20522076 + ... + 20522172.

It is an arithmetic number, because the mean of its divisors is an integer number (21688576).

Almost surely, 2^1990646028 is an apocalyptic number.

1990646028 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 1990646028, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3123154944).

1990646028 is an abundant number, since it is smaller than the sum of its proper divisors (4255663860).

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

1990646028 is a wasteful number, since it uses less digits than its factorization.

1990646028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253 (or 248 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 1990646028 is about 44616.6563964625. The cubic root of 1990646028 is about 1257.9537686804.

The spelling of 1990646028 in words is "one billion, nine hundred ninety million, six hundred forty-six thousand, twenty-eight".