1221171607 has 2 divisors, whose sum is σ = 1221171608. Its totient is φ = 1221171606.

The previous prime is 1221171587. The next prime is 1221171647. The reversal of 1221171607 is 7061711221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221171607 - 2¹⁹ = 1220647319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221171647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610585803 + 610585804.

It is an arithmetic number, because the mean of its divisors is an integer number (610585804).

Almost surely, 2^1221171607 is an apocalyptic number.

1221171607 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221171607 is an equidigital number, since it uses as much as digits as its factorization.

1221171607 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1176, while the sum is 28.

The square root of 1221171607 is about 34945.2658739349. The cubic root of 1221171607 is about 1068.8716690502.

Adding to 1221171607 its reverse (7061711221), we get a palindrome (8282882828).

The spelling of 1221171607 in words is "one billion, two hundred twenty-one million, one hundred seventy-one thousand, six hundred seven".