20519998 has 4 divisors (see below), whose sum is σ = 30780000. Its totient is φ = 10259998.

The previous prime is 20519977. The next prime is 20520029. The reversal of 20519998 is 89991502.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5129998 + ... + 5130001.

It is an arithmetic number, because the mean of its divisors is an integer number (7695000).

Almost surely, 2^20519998 is an apocalyptic number.

20519998 is a deficient number, since it is larger than the sum of its proper divisors (10260002).

20519998 is a wasteful number, since it uses less digits than its factorization.

20519998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10260001.

The product of its (nonzero) digits is 58320, while the sum is 43.

The square root of 20519998 is about 4529.9004404071. The cubic root of 20519998 is about 273.7741492287.

The spelling of 20519998 in words is "twenty million, five hundred nineteen thousand, nine hundred ninety-eight".