20021113131 has 4 divisors (see below), whose sum is σ = 26694817512. Its totient is φ = 13347408752.

The previous prime is 20021113127. The next prime is 20021113207. The reversal of 20021113131 is 13131112002.

It is a happy number.

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 20021113131 - 2² = 20021113127 is a prime.

It is a super-2 number, since 2×20021113131² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20021113131.

It is not an unprimeable number, because it can be changed into a prime (20025113131) 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, 3336852186 + ... + 3336852191.

It is an arithmetic number, because the mean of its divisors is an integer number (6673704378).

Almost surely, 2^20021113131 is an apocalyptic number.

20021113131 is a deficient number, since it is larger than the sum of its proper divisors (6673704381).

20021113131 is an equidigital number, since it uses as much as digits as its factorization.

20021113131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6673704380.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 20021113131 its reverse (13131112002), we get a palindrome (33152225133).

The spelling of 20021113131 in words is "twenty billion, twenty-one million, one hundred thirteen thousand, one hundred thirty-one".