172947213 has 24 divisors (see below), whose sum is σ = 265426200. Its totient is φ = 108307584.

The previous prime is 172947193. The next prime is 172947227. The reversal of 172947213 is 312749271.

172947213 is a `hidden beast` number, since 172 + 9 + 472 + 13 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 55398249 + 117548964 = 7443^2 + 10842^2 .

It is not a de Polignac number, because 172947213 - 2⁶ = 172947149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172947013) 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, 703 + ... + 18611.

It is an arithmetic number, because the mean of its divisors is an integer number (11059425).

Almost surely, 2^172947213 is an apocalyptic number.

It is an amenable number.

172947213 is a deficient number, since it is larger than the sum of its proper divisors (92478987).

172947213 is a wasteful number, since it uses less digits than its factorization.

172947213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17981 (or 17978 counting only the distinct ones).

The product of its digits is 21168, while the sum is 36.

The square root of 172947213 is about 13150.9396242246. The cubic root of 172947213 is about 557.1487869473.

The spelling of 172947213 in words is "one hundred seventy-two million, nine hundred forty-seven thousand, two hundred thirteen".