20402843209 has 8 divisors (see below), whose sum is σ = 23813653248. Its totient is φ = 17116062720.

The previous prime is 20402843191. The next prime is 20402843213. The reversal of 20402843209 is 90234820402.

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 20402843209 - 2⁷ = 20402843081 is a prime.

It is a super-2 number, since 2×20402843209² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20402843239) 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, 31007032 + ... + 31007689.

It is an arithmetic number, because the mean of its divisors is an integer number (2976706656).

Almost surely, 2^20402843209 is an apocalyptic number.

It is an amenable number.

20402843209 is a deficient number, since it is larger than the sum of its proper divisors (3410810039).

20402843209 is an equidigital number, since it uses as much as digits as its factorization.

20402843209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62014775.

The product of its (nonzero) digits is 27648, while the sum is 34.

The spelling of 20402843209 in words is "twenty billion, four hundred two million, eight hundred forty-three thousand, two hundred nine".