1211162021 has 2 divisors, whose sum is σ = 1211162022. Its totient is φ = 1211162020.

The previous prime is 1211161999. The next prime is 1211162039. The reversal of 1211162021 is 1202611121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 977500225 + 233661796 = 31265^2 + 15286^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211162021 is a prime.

It is a super-2 number, since 2×1211162021² = 2933826882225608882, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1211162081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605581010 + 605581011.

It is an arithmetic number, because the mean of its divisors is an integer number (605581011).

Almost surely, 2^1211162021 is an apocalyptic number.

It is an amenable number.

1211162021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211162021 is an equidigital number, since it uses as much as digits as its factorization.

1211162021 is an evil number, because the sum of its binary digits is even.

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

The square root of 1211162021 is about 34801.7531311283. The cubic root of 1211162021 is about 1065.9432439302.

Adding to 1211162021 its reverse (1202611121), we get a palindrome (2413773142).

The spelling of 1211162021 in words is "one billion, two hundred eleven million, one hundred sixty-two thousand, twenty-one".