211001011221 has 192 divisors, whose sum is σ = 393936721920. Its totient is φ = 96944325120.

The previous prime is 211001011217. The next prime is 211001011261. The reversal of 211001011221 is 122110100112.

It is not a de Polignac number, because 211001011221 - 2² = 211001011217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 211001011197 and 211001011206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211001011261) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1178776510 + ... + 1178776688.

It is an arithmetic number, because the mean of its divisors is an integer number (2051753760).

Almost surely, 2^211001011221 is an apocalyptic number.

211001011221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

211001011221 is a deficient number, since it is larger than the sum of its proper divisors (182935710699).

211001011221 is a wasteful number, since it uses less digits than its factorization.

211001011221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456 (or 353 counting only the distinct ones).

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

Adding to 211001011221 its reverse (122110100112), we get a palindrome (333111111333).

The spelling of 211001011221 in words is "two hundred eleven billion, one million, eleven thousand, two hundred twenty-one".