20199863 has 4 divisors (see below), whose sum is σ = 20896440. Its totient is φ = 19503288.

The previous prime is 20199847. The next prime is 20199901. The reversal of 20199863 is 36899102.

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 20199863 - 2⁴ = 20199847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20193863) 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, 348245 + ... + 348302.

It is an arithmetic number, because the mean of its divisors is an integer number (5224110).

Almost surely, 2^20199863 is an apocalyptic number.

20199863 is a deficient number, since it is larger than the sum of its proper divisors (696577).

20199863 is an equidigital number, since it uses as much as digits as its factorization.

20199863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696576.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 20199863 is about 4494.4257697730. The cubic root of 20199863 is about 272.3429524613.

The spelling of 20199863 in words is "twenty million, one hundred ninety-nine thousand, eight hundred sixty-three".