1221193899 has 6 divisors (see below), whose sum is σ = 1763946756. Its totient is φ = 814129260.

The previous prime is 1221193877. The next prime is 1221193907. The reversal of 1221193899 is 9983911221.

It is not a de Polignac number, because 1221193899 - 2⁸ = 1221193643 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221191899) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 67844097 + ... + 67844114.

It is an arithmetic number, because the mean of its divisors is an integer number (293991126).

Almost surely, 2^1221193899 is an apocalyptic number.

1221193899 is a deficient number, since it is larger than the sum of its proper divisors (542752857).

1221193899 is a wasteful number, since it uses less digits than its factorization.

1221193899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135688217 (or 135688214 counting only the distinct ones).

The product of its digits is 69984, while the sum is 45.

The square root of 1221193899 is about 34945.5848284157. The cubic root of 1221193899 is about 1068.8781729525.

The spelling of 1221193899 in words is "one billion, two hundred twenty-one million, one hundred ninety-three thousand, eight hundred ninety-nine".