172438305 has 24 divisors (see below), whose sum is σ = 298761408. Its totient is φ = 84891456.

The previous prime is 172438267. The next prime is 172438307. The reversal of 172438305 is 503834271.

It is not a de Polignac number, because 172438305 - 2⁷ = 172438177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (172438307) 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, 31477 + ... + 36546.

It is an arithmetic number, because the mean of its divisors is an integer number (12448392).

Almost surely, 2^172438305 is an apocalyptic number.

172438305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

172438305 is a deficient number, since it is larger than the sum of its proper divisors (126323103).

172438305 is a wasteful number, since it uses less digits than its factorization.

172438305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68057 (or 68044 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 172438305 is about 13131.5766380127. The cubic root of 172438305 is about 556.6017683235.

The spelling of 172438305 in words is "one hundred seventy-two million, four hundred thirty-eight thousand, three hundred five".