1221671208 has 16 divisors (see below), whose sum is σ = 3054178080. Its totient is φ = 407223728.

The previous prime is 1221671207. The next prime is 1221671251. The reversal of 1221671208 is 8021761221.

It is not an unprimeable number, because it can be changed into a prime (1221671201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25451460 + ... + 25451507.

It is an arithmetic number, because the mean of its divisors is an integer number (190886130).

Almost surely, 2^1221671208 is an apocalyptic number.

It is an amenable number.

1221671208 is an abundant number, since it is smaller than the sum of its proper divisors (1832506872).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221671208 is a wasteful number, since it uses less digits than its factorization.

1221671208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50902976 (or 50902972 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 1221671208 is about 34952.4134789001. The cubic root of 1221671208 is about 1069.0174133896.

The spelling of 1221671208 in words is "one billion, two hundred twenty-one million, six hundred seventy-one thousand, two hundred eight".