2156220012 has 24 divisors (see below), whose sum is σ = 5153892912. Its totient is φ = 701209600.

The previous prime is 2156219981. The next prime is 2156220019. The reversal of 2156220012 is 2100226512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (2156220019) 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, 2190789 + ... + 2191772.

It is an arithmetic number, because the mean of its divisors is an integer number (214745538).

Almost surely, 2^2156220012 is an apocalyptic number.

It is an amenable number.

2156220012 is an abundant number, since it is smaller than the sum of its proper divisors (2997672900).

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

2156220012 is a wasteful number, since it uses less digits than its factorization.

2156220012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4382609 (or 4382607 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 2156220012 is about 46435.1161514645. The cubic root of 2156220012 is about 1291.9063239823.

Adding to 2156220012 its reverse (2100226512), we get a palindrome (4256446524).

The spelling of 2156220012 in words is "two billion, one hundred fifty-six million, two hundred twenty thousand, twelve".