1221720882 has 8 divisors (see below), whose sum is σ = 2443441776. Its totient is φ = 407240292.

The previous prime is 1221720839. The next prime is 1221720883. The reversal of 1221720882 is 2880271221.

It is a sphenic number, since it is the product of 3 distinct primes.

1221720882 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (1221720883) 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, 101810068 + ... + 101810079.

It is an arithmetic number, because the mean of its divisors is an integer number (305430222).

Almost surely, 2^1221720882 is an apocalyptic number.

1221720882 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1221720882 is a wasteful number, since it uses less digits than its factorization.

1221720882 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203620152.

The product of its (nonzero) digits is 7168, while the sum is 33.

The square root of 1221720882 is about 34953.1240663835. The cubic root of 1221720882 is about 1069.0319021901.

The spelling of 1221720882 in words is "one billion, two hundred twenty-one million, seven hundred twenty thousand, eight hundred eighty-two".