21001221241011 has 24 divisors (see below), whose sum is σ = 33862434255936. Its totient is φ = 12432012571440.

The previous prime is 21001221241009. The next prime is 21001221241027. The reversal of 21001221241011 is 11014212210012.

21001221241011 is a `hidden beast` number, since 21 + 0 + 0 + 1 + 221 + 2 + 410 + 11 = 666.

It is not a de Polignac number, because 21001221241011 - 2¹ = 21001221241009 is a prime.

It is a super-2 number, since 2×21001221241011² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21001221241411) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2466664905 + ... + 2466673418.

It is an arithmetic number, because the mean of its divisors is an integer number (1410934760664).

Almost surely, 2^{21001221241011} is an apocalyptic number.

21001221241011 is a deficient number, since it is larger than the sum of its proper divisors (12861213014925).

21001221241011 is a wasteful number, since it uses less digits than its factorization.

21001221241011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4933338383 (or 4933338380 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21001221241011 its reverse (11014212210012), we get a palindrome (32015433451023).

The spelling of 21001221241011 in words is "twenty-one trillion, one billion, two hundred twenty-one million, two hundred forty-one thousand, eleven".