2155717228 has 96 divisors (see below), whose sum is σ = 4667572224. Its totient is φ = 851197248.

The previous prime is 2155717171. The next prime is 2155717243. The reversal of 2155717228 is 8227175512.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2027425 + ... + 2028487.

It is an arithmetic number, because the mean of its divisors is an integer number (48620544).

Almost surely, 2^2155717228 is an apocalyptic number.

2155717228 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2155717228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2333786112).

2155717228 is an abundant number, since it is smaller than the sum of its proper divisors (2511854996).

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

2155717228 is a wasteful number, since it uses less digits than its factorization.

2155717228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1211 (or 1209 counting only the distinct ones).

The product of its digits is 78400, while the sum is 40.

The square root of 2155717228 is about 46429.7020020590. The cubic root of 2155717228 is about 1291.8059012798.

The spelling of 2155717228 in words is "two billion, one hundred fifty-five million, seven hundred seventeen thousand, two hundred twenty-eight".