21311332011 has 16 divisors (see below), whose sum is σ = 31576309120. Its totient is φ = 14205770280.

The previous prime is 21311331997. The next prime is 21311332057. The reversal of 21311332011 is 11023311312.

21311332011 is a `hidden beast` number, since 21 + 311 + 3 + 320 + 11 = 666.

It is not a de Polignac number, because 21311332011 - 2⁶ = 21311331947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21311332411) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 190536 + ... + 280938.

It is an arithmetic number, because the mean of its divisors is an integer number (1973519320).

Almost surely, 2^21311332011 is an apocalyptic number.

21311332011 is a deficient number, since it is larger than the sum of its proper divisors (10264977109).

21311332011 is an equidigital number, since it uses as much as digits as its factorization.

21311332011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99143 (or 99137 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21311332011 its reverse (11023311312), we get a palindrome (32334643323).

The spelling of 21311332011 in words is "twenty-one billion, three hundred eleven million, three hundred thirty-two thousand, eleven".