1221701606 has 4 divisors (see below), whose sum is σ = 1832552412. Its totient is φ = 610850802.

The previous prime is 1221701581. The next prime is 1221701627. The reversal of 1221701606 is 6061071221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6061071221 = 307 ⋅19742903.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305425400 + ... + 305425403.

It is an arithmetic number, because the mean of its divisors is an integer number (458138103).

Almost surely, 2^1221701606 is an apocalyptic number.

1221701606 is a deficient number, since it is larger than the sum of its proper divisors (610850806).

1221701606 is an equidigital number, since it uses as much as digits as its factorization.

1221701606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610850805.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 1221701606 is about 34952.8483245643. The cubic root of 1221701606 is about 1069.0262798565.

Adding to 1221701606 its reverse (6061071221), we get a palindrome (7282772827).

The spelling of 1221701606 in words is "one billion, two hundred twenty-one million, seven hundred one thousand, six hundred six".