1211665057 has 2 divisors, whose sum is σ = 1211665058. Its totient is φ = 1211665056.

The previous prime is 1211665033. The next prime is 1211665061. The reversal of 1211665057 is 7505661121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1208535696 + 3129361 = 34764^2 + 1769^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211665057 - 2⁷ = 1211664929 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211665097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605832528 + 605832529.

It is an arithmetic number, because the mean of its divisors is an integer number (605832529).

Almost surely, 2^1211665057 is an apocalyptic number.

It is an amenable number.

1211665057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211665057 is an equidigital number, since it uses as much as digits as its factorization.

1211665057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12600, while the sum is 34.

The square root of 1211665057 is about 34808.9795455138. The cubic root of 1211665057 is about 1066.0907974362.

The spelling of 1211665057 in words is "one billion, two hundred eleven million, six hundred sixty-five thousand, fifty-seven".