1221719412 has 12 divisors (see below), whose sum is σ = 2850678656. Its totient is φ = 407239800.

The previous prime is 1221719381. The next prime is 1221719417. The reversal of 1221719412 is 2149171221.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 1221719412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221719417) 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, 50904964 + ... + 50904987.

Almost surely, 2^1221719412 is an apocalyptic number.

1221719412 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221719412 is an abundant number, since it is smaller than the sum of its proper divisors (1628959244).

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

1221719412 is a wasteful number, since it uses less digits than its factorization.

1221719412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101809958 (or 101809956 counting only the distinct ones).

The product of its digits is 2016, while the sum is 30.

The square root of 1221719412 is about 34953.1030382139. The cubic root of 1221719412 is about 1069.0314734295.

The spelling of 1221719412 in words is "one billion, two hundred twenty-one million, seven hundred nineteen thousand, four hundred twelve".