201211211381 has 2 divisors, whose sum is σ = 201211211382. Its totient is φ = 201211211380.

The previous prime is 201211211323. The next prime is 201211211401. The reversal of 201211211381 is 183112112102.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 201182749156 + 28462225 = 448534^2 + 5335^2 .

It is a cyclic number.

It is not a de Polignac number, because 201211211381 - 2⁶ = 201211211317 is a prime.

It is a super-2 number, since 2×201211211381² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201211213381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100605605690 + 100605605691.

It is an arithmetic number, because the mean of its divisors is an integer number (100605605691).

Almost surely, 2^201211211381 is an apocalyptic number.

It is an amenable number.

201211211381 is a deficient number, since it is larger than the sum of its proper divisors (1).

201211211381 is an equidigital number, since it uses as much as digits as its factorization.

201211211381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 23.

Adding to 201211211381 its reverse (183112112102), we get a palindrome (384323323483).

The spelling of 201211211381 in words is "two hundred one billion, two hundred eleven million, two hundred eleven thousand, three hundred eighty-one".