1219791221 has 8 divisors (see below), whose sum is σ = 1331553600. Its totient is φ = 1108174240.

The previous prime is 1219791217. The next prime is 1219791229. The reversal of 1219791221 is 1221979121.

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

It is a cyclic number.

It is not a de Polignac number, because 1219791221 - 2² = 1219791217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1219791229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18416 + ... + 52713.

It is an arithmetic number, because the mean of its divisors is an integer number (166444200).

Almost surely, 2^1219791221 is an apocalyptic number.

1219791221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1219791221 is a deficient number, since it is larger than the sum of its proper divisors (111762379).

1219791221 is a wasteful number, since it uses less digits than its factorization.

1219791221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72699.

The product of its digits is 4536, while the sum is 35.

The square root of 1219791221 is about 34925.5096025813. The cubic root of 1219791221 is about 1068.4687740572.

The spelling of 1219791221 in words is "one billion, two hundred nineteen million, seven hundred ninety-one thousand, two hundred twenty-one".