1221830916 has 12 divisors (see below), whose sum is σ = 2850938832. Its totient is φ = 407276968.

The previous prime is 1221830887. The next prime is 1221830917. The reversal of 1221830916 is 6190381221.

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

It is not an unprimeable number, because it can be changed into a prime (1221830917) 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, 50909610 + ... + 50909633.

It is an arithmetic number, because the mean of its divisors is an integer number (237578236).

Almost surely, 2^1221830916 is an apocalyptic number.

It is an amenable number.

1221830916 is an abundant number, since it is smaller than the sum of its proper divisors (1629107916).

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

1221830916 is a wasteful number, since it uses less digits than its factorization.

1221830916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101819250 (or 101819248 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 1221830916 is about 34954.6980533376. The cubic root of 1221830916 is about 1069.0639952611.

It can be divided in two parts, 12218 and 30916, that added together give a palindrome (43134).

The spelling of 1221830916 in words is "one billion, two hundred twenty-one million, eight hundred thirty thousand, nine hundred sixteen".