2121219920 has 40 divisors (see below), whose sum is σ = 5015437920. Its totient is φ = 834104960.

The previous prime is 2121219899. The next prime is 2121219929. The reversal of 2121219920 is 299121212.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121219929) 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, 219986 + ... + 229425.

It is an arithmetic number, because the mean of its divisors is an integer number (125385948).

Almost surely, 2^2121219920 is an apocalyptic number.

2121219920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121219920 is an abundant number, since it is smaller than the sum of its proper divisors (2894218000).

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

2121219920 is a wasteful number, since it uses less digits than its factorization.

2121219920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449483 (or 449477 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 2121219920 is about 46056.7033123301. The cubic root of 2121219920 is about 1284.8780173589.

The spelling of 2121219920 in words is "two billion, one hundred twenty-one million, two hundred nineteen thousand, nine hundred twenty".