21001210111211 has 8 divisors (see below), whose sum is σ = 22991942745648. Its totient is φ = 19024066096000.

The previous prime is 21001210111201. The next prime is 21001210111243. The reversal of 21001210111211 is 11211101210012.

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 21001210111211 - 2¹⁰ = 21001210110187 is a prime.

It is a super-2 number, since 2×21001210111211² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21001210111201) 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, 3397151570 + ... + 3397157751.

It is an arithmetic number, because the mean of its divisors is an integer number (2873992843206).

Almost surely, 2^{21001210111211} is an apocalyptic number.

21001210111211 is a deficient number, since it is larger than the sum of its proper divisors (1990732634437).

21001210111211 is a wasteful number, since it uses less digits than its factorization.

21001210111211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6794309613.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21001210111211 its reverse (11211101210012), we get a palindrome (32212311321223).

The spelling of 21001210111211 in words is "twenty-one trillion, one billion, two hundred ten million, one hundred eleven thousand, two hundred eleven".