20131220011 has 4 divisors (see below), whose sum is σ = 23007108592. Its totient is φ = 17255331432.

The previous prime is 20131220003. The next prime is 20131220017. The reversal of 20131220011 is 11002213102.

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 20131220011 - 2³ = 20131220003 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20131219973 and 20131220000.

It is not an unprimeable number, because it can be changed into a prime (20131220017) 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, 1437944280 + ... + 1437944293.

It is an arithmetic number, because the mean of its divisors is an integer number (5751777148).

Almost surely, 2^20131220011 is an apocalyptic number.

20131220011 is a deficient number, since it is larger than the sum of its proper divisors (2875888581).

20131220011 is an equidigital number, since it uses as much as digits as its factorization.

20131220011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2875888580.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 20131220011 its reverse (11002213102), we get a palindrome (31133433113).

The spelling of 20131220011 in words is "twenty billion, one hundred thirty-one million, two hundred twenty thousand, eleven".