121771649 has 2 divisors, whose sum is σ = 121771650. Its totient is φ = 121771648.

The previous prime is 121771619. The next prime is 121771673. The reversal of 121771649 is 946177121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 86583025 + 35188624 = 9305^2 + 5932^2 .

It is an emirp because it is prime and its reverse (946177121) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121771649 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (121771619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60885824 + 60885825.

It is an arithmetic number, because the mean of its divisors is an integer number (60885825).

Almost surely, 2^121771649 is an apocalyptic number.

It is an amenable number.

121771649 is a deficient number, since it is larger than the sum of its proper divisors (1).

121771649 is an equidigital number, since it uses as much as digits as its factorization.

121771649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21168, while the sum is 38.

The square root of 121771649 is about 11035.0192115827. The cubic root of 121771649 is about 495.6579340781.

The spelling of 121771649 in words is "one hundred twenty-one million, seven hundred seventy-one thousand, six hundred forty-nine".