20519988 has 12 divisors (see below), whose sum is σ = 47880000. Its totient is φ = 6839992.

The previous prime is 20519977. The next prime is 20520029. The reversal of 20519988 is 88991502.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 854988 + ... + 855011.

It is an arithmetic number, because the mean of its divisors is an integer number (3990000).

Almost surely, 2^20519988 is an apocalyptic number.

It is an amenable number.

20519988 is an abundant number, since it is smaller than the sum of its proper divisors (27360012).

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

20519988 is a wasteful number, since it uses less digits than its factorization.

20519988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1710006 (or 1710004 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 20519988 is about 4529.8993366299. The cubic root of 20519988 is about 273.7741047559.

The spelling of 20519988 in words is "twenty million, five hundred nineteen thousand, nine hundred eighty-eight".