21121102011 has 8 divisors (see below), whose sum is σ = 28164435520. Its totient is φ = 14079251592.

The previous prime is 21121101997. The next prime is 21121102049. The reversal of 21121102011 is 11020112112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21121102011 - 2¹⁴ = 21121085627 is a prime.

It is a super-2 number, since 2×21121102011² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21121102091) 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, 337105 + ... + 394818.

It is an arithmetic number, because the mean of its divisors is an integer number (3520554440).

Almost surely, 2^21121102011 is an apocalyptic number.

21121102011 is a deficient number, since it is larger than the sum of its proper divisors (7043333509).

21121102011 is an equidigital number, since it uses as much as digits as its factorization.

21121102011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741545.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21121102011 its reverse (11020112112), we get a palindrome (32141214123).

It can be divided in two parts, 2112 and 1102011, that multiplied together give a palindrome (2327447232).

The spelling of 21121102011 in words is "twenty-one billion, one hundred twenty-one million, one hundred two thousand, eleven".