2221620156 has 96 divisors (see below), whose sum is σ = 6760570880. Its totient is φ = 617585472.

The previous prime is 2221620143. The next prime is 2221620199. The reversal of 2221620156 is 6510261222.

2221620156 is a `hidden beast` number, since 2 + 2 + 21 + 620 + 15 + 6 = 666.

It is a super-2 number, since 2×2221620156² = 9871192235090928672, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11740 + ... + 67683.

Almost surely, 2^2221620156 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2221620156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3380285440).

2221620156 is an abundant number, since it is smaller than the sum of its proper divisors (4538950724).

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

2221620156 is a wasteful number, since it uses less digits than its factorization.

2221620156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79480 (or 79472 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 2221620156 is about 47134.0657698866. The cubic root of 2221620156 is about 1304.8380192664.

Adding to 2221620156 its reverse (6510261222), we get a palindrome (8731881378).

The spelling of 2221620156 in words is "two billion, two hundred twenty-one million, six hundred twenty thousand, one hundred fifty-six".