2172787644 has 48 divisors (see below), whose sum is σ = 5460940800. Its totient is φ = 670422720.

The previous prime is 2172787637. The next prime is 2172787657. The reversal of 2172787644 is 4467872712.

It is a super-2 number, since 2×2172787644² = 9442012291838141472, which contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 2172787593 and 2172787602.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118419 + ... + 135530.

It is an arithmetic number, because the mean of its divisors is an integer number (113769600).

Almost surely, 2^2172787644 is an apocalyptic number.

It is an amenable number.

2172787644 is an abundant number, since it is smaller than the sum of its proper divisors (3288153156).

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

2172787644 is a wasteful number, since it uses less digits than its factorization.

2172787644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254010 (or 254008 counting only the distinct ones).

The product of its digits is 1053696, while the sum is 48.

The square root of 2172787644 is about 46613.1702848026. The cubic root of 2172787644 is about 1295.2067357270.

The spelling of 2172787644 in words is "two billion, one hundred seventy-two million, seven hundred eighty-seven thousand, six hundred forty-four".