20509019859 has 8 divisors (see below), whose sum is σ = 27370156032. Its totient is φ = 13660281800.

The previous prime is 20509019857. The next prime is 20509019887. The reversal of 20509019859 is 95891090502.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20509019859 - 2¹ = 20509019857 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20509019857) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3095667 + ... + 3102284.

It is an arithmetic number, because the mean of its divisors is an integer number (3421269504).

Almost surely, 2^20509019859 is an apocalyptic number.

20509019859 is a deficient number, since it is larger than the sum of its proper divisors (6861136173).

20509019859 is a wasteful number, since it uses less digits than its factorization.

20509019859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6199057.

The product of its (nonzero) digits is 291600, while the sum is 48.

The spelling of 20509019859 in words is "twenty billion, five hundred nine million, nineteen thousand, eight hundred fifty-nine".