1227841661 has 2 divisors, whose sum is σ = 1227841662. Its totient is φ = 1227841660.

The previous prime is 1227841631. The next prime is 1227841663. The reversal of 1227841661 is 1661487221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1113223225 + 114618436 = 33365^2 + 10706^2 .

It is a cyclic number.

It is not a de Polignac number, because 1227841661 - 2¹⁸ = 1227579517 is a prime.

Together with 1227841663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1227841663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 613920830 + 613920831.

It is an arithmetic number, because the mean of its divisors is an integer number (613920831).

Almost surely, 2^1227841661 is an apocalyptic number.

It is an amenable number.

1227841661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1227841661 is an equidigital number, since it uses as much as digits as its factorization.

1227841661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32256, while the sum is 38.

The square root of 1227841661 is about 35040.5716420266. The cubic root of 1227841661 is about 1070.8141999249.

The spelling of 1227841661 in words is "one billion, two hundred twenty-seven million, eight hundred forty-one thousand, six hundred sixty-one".