172520647 has 4 divisors (see below), whose sum is σ = 185791480. Its totient is φ = 159249816.

The previous prime is 172520639. The next prime is 172520651. The reversal of 172520647 is 746025271.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 172520647 - 2³ = 172520639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172520147) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 6635397 + ... + 6635422.

It is an arithmetic number, because the mean of its divisors is an integer number (46447870).

Almost surely, 2^172520647 is an apocalyptic number.

172520647 is a deficient number, since it is larger than the sum of its proper divisors (13270833).

172520647 is a wasteful number, since it uses less digits than its factorization.

172520647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13270832.

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 172520647 is about 13134.7115309016. The cubic root of 172520647 is about 556.6903495886.

The spelling of 172520647 in words is "one hundred seventy-two million, five hundred twenty thousand, six hundred forty-seven".