2172647521 has 8 divisors (see below), whose sum is σ = 2420590464. Its totient is φ = 1933109520.

The previous prime is 2172647507. The next prime is 2172647527. The reversal of 2172647521 is 1257462712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2172647521 - 2²³ = 2164258913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2172647527) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2100690 + ... + 2101723.

It is an arithmetic number, because the mean of its divisors is an integer number (302573808).

Almost surely, 2^2172647521 is an apocalyptic number.

It is an amenable number.

2172647521 is a deficient number, since it is larger than the sum of its proper divisors (247942943).

2172647521 is a wasteful number, since it uses less digits than its factorization.

2172647521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4202471.

The product of its digits is 47040, while the sum is 37.

The square root of 2172647521 is about 46611.6672196994. The cubic root of 2172647521 is about 1295.1788925159.

It can be divided in two parts, 217264 and 7521, that added together give a triangular number (224785 = T₆₇₀).

The spelling of 2172647521 in words is "two billion, one hundred seventy-two million, six hundred forty-seven thousand, five hundred twenty-one".