1990388508 has 48 divisors (see below), whose sum is σ = 4835177760. Its totient is φ = 636678144.

The previous prime is 1990388503. The next prime is 1990388549. The reversal of 1990388508 is 8058830991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990388503) 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 15 ways as a sum of consecutive naturals, for example, 1708 + ... + 63116.

It is an arithmetic number, because the mean of its divisors is an integer number (100732870).

Almost surely, 2^1990388508 is an apocalyptic number.

It is an amenable number.

1990388508 is an abundant number, since it is smaller than the sum of its proper divisors (2844789252).

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

1990388508 is a wasteful number, since it uses less digits than its factorization.

1990388508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61526 (or 61524 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 51.

The square root of 1990388508 is about 44613.7703853866. The cubic root of 1990388508 is about 1257.8995212619.

The spelling of 1990388508 in words is "one billion, nine hundred ninety million, three hundred eighty-eight thousand, five hundred eight".