21311121011 has 8 divisors (see below), whose sum is σ = 21632763024. Its totient is φ = 20989584000.

The previous prime is 21311120981. The next prime is 21311121043. The reversal of 21311121011 is 11012111312.

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 21311121011 - 2⁶ = 21311120947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21311120011) 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, 446351 + ... + 491783.

It is an arithmetic number, because the mean of its divisors is an integer number (2704095378).

Almost surely, 2^21311121011 is an apocalyptic number.

21311121011 is a deficient number, since it is larger than the sum of its proper divisors (321642013).

21311121011 is an equidigital number, since it uses as much as digits as its factorization.

21311121011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52501.

The product of its (nonzero) digits is 12, while the sum is 14.

Adding to 21311121011 its reverse (11012111312), we get a palindrome (32323232323).

The spelling of 21311121011 in words is "twenty-one billion, three hundred eleven million, one hundred twenty-one thousand, eleven".