20198659 has 4 divisors (see below), whose sum is σ = 21752416. Its totient is φ = 18644904.

The previous prime is 20198657. The next prime is 20198713. The reversal of 20198659 is 95689102.

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

It is a cyclic number.

It is not a de Polignac number, because 20198659 - 2¹ = 20198657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20198657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 776859 + ... + 776884.

It is an arithmetic number, because the mean of its divisors is an integer number (5438104).

Almost surely, 2^20198659 is an apocalyptic number.

20198659 is a deficient number, since it is larger than the sum of its proper divisors (1553757).

20198659 is a wasteful number, since it uses less digits than its factorization.

20198659 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1553756.

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 20198659 is about 4494.2918240809. The cubic root of 20198659 is about 272.3375414109.

The spelling of 20198659 in words is "twenty million, one hundred ninety-eight thousand, six hundred fifty-nine".