2172155240 has 64 divisors (see below), whose sum is σ = 5156524800. Its totient is φ = 821221632.

The previous prime is 2172155239. The next prime is 2172155281. The reversal of 2172155240 is 425512712.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 348794 + ... + 354966.

It is an arithmetic number, because the mean of its divisors is an integer number (80570700).

Almost surely, 2^2172155240 is an apocalyptic number.

2172155240 is a gapful number since it is divisible by the number (20) 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 2172155240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2578262400).

2172155240 is an abundant number, since it is smaller than the sum of its proper divisors (2984369560).

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

2172155240 is a wasteful number, since it uses less digits than its factorization.

2172155240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6666 (or 6662 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 29.

The square root of 2172155240 is about 46606.3862576793. The cubic root of 2172155240 is about 1295.0810640807.

Adding to 2172155240 its reverse (425512712), we get a palindrome (2597667952).

The spelling of 2172155240 in words is "two billion, one hundred seventy-two million, one hundred fifty-five thousand, two hundred forty".