2172653640 has 96 divisors (see below), whose sum is σ = 7081214400. Its totient is φ = 577726080.

The previous prime is 2172653633. The next prime is 2172653641. The reversal of 2172653640 is 463562712.

2172653640 is a `hidden beast` number, since 2 + 1 + 7 + 2 + 6 + 5 + 3 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2172653595 and 2172653604.

It is not an unprimeable number, because it can be changed into a prime (2172653641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 120835 + ... + 137645.

It is an arithmetic number, because the mean of its divisors is an integer number (73762650).

Almost surely, 2^2172653640 is an apocalyptic number.

2172653640 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 2172653640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3540607200).

2172653640 is an abundant number, since it is smaller than the sum of its proper divisors (4908560760).

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

2172653640 is a wasteful number, since it uses less digits than its factorization.

2172653640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17187 (or 17180 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The square root of 2172653640 is about 46611.7328577259. The cubic root of 2172653640 is about 1295.1801084199.

The spelling of 2172653640 in words is "two billion, one hundred seventy-two million, six hundred fifty-three thousand, six hundred forty".