21121232011 has 16 divisors (see below), whose sum is σ = 23393691648. Its totient is φ = 18908142400.

The previous prime is 21121232003. The next prime is 21121232053. The reversal of 21121232011 is 11023212112.

It is a cyclic number.

It is not a de Polignac number, because 21121232011 - 2³ = 21121232003 is a prime.

It is a super-3 number, since 3×21121232011³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21121632011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 658335 + ... + 689671.

It is an arithmetic number, because the mean of its divisors is an integer number (1462105728).

Almost surely, 2^21121232011 is an apocalyptic number.

21121232011 is a deficient number, since it is larger than the sum of its proper divisors (2272459637).

21121232011 is a wasteful number, since it uses less digits than its factorization.

21121232011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32282.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21121232011 its reverse (11023212112), we get a palindrome (32144444123).

The spelling of 21121232011 in words is "twenty-one billion, one hundred twenty-one million, two hundred thirty-two thousand, eleven".