1990518556 has 24 divisors (see below), whose sum is σ = 3872376704. Its totient is φ = 889064640.

The previous prime is 1990518529. The next prime is 1990518557. The reversal of 1990518556 is 6558150991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990518557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 615795 + ... + 619018.

Almost surely, 2^1990518556 is an apocalyptic number.

It is an amenable number.

1990518556 is a deficient number, since it is larger than the sum of its proper divisors (1881858148).

1990518556 is a wasteful number, since it uses less digits than its factorization.

1990518556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1234861 (or 1234859 counting only the distinct ones).

The product of its (nonzero) digits is 486000, while the sum is 49.

The square root of 1990518556 is about 44615.2278487962. The cubic root of 1990518556 is about 1257.9269168773.

The spelling of 1990518556 in words is "one billion, nine hundred ninety million, five hundred eighteen thousand, five hundred fifty-six".