1211381 has 2 divisors, whose sum is σ = 1211382. Its totient is φ = 1211380.

The previous prime is 1211339. The next prime is 1211389. The reversal of 1211381 is 1831121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 707281 + 504100 = 841^2 + 710^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211381 - 2¹⁴ = 1194997 is a prime.

It is a super-2 number, since 2×1211381² = 2934887854322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211389) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605690 + 605691.

It is an arithmetic number, because the mean of its divisors is an integer number (605691).

2^1211381 is an apocalyptic number.

It is an amenable number.

1211381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211381 is an equidigital number, since it uses as much as digits as its factorization.

1211381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48, while the sum is 17.

The square root of 1211381 is about 1100.6275482651. The cubic root of 1211381 is about 106.6007481171.

The spelling of 1211381 in words is "one million, two hundred eleven thousand, three hundred eighty-one".