1221287159 has 2 divisors, whose sum is σ = 1221287160. Its totient is φ = 1221287158.

The previous prime is 1221287141. The next prime is 1221287167. The reversal of 1221287159 is 9517821221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221287159 - 2²⁰ = 1220238583 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221287959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610643579 + 610643580.

It is an arithmetic number, because the mean of its divisors is an integer number (610643580).

Almost surely, 2^1221287159 is an apocalyptic number.

1221287159 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221287159 is an equidigital number, since it uses as much as digits as its factorization.

1221287159 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 38.

The square root of 1221287159 is about 34946.9191632109. The cubic root of 1221287159 is about 1068.9053815831.

The spelling of 1221287159 in words is "one billion, two hundred twenty-one million, two hundred eighty-seven thousand, one hundred fifty-nine".