172897993 has 4 divisors (see below), whose sum is σ = 175333248. Its totient is φ = 170462740.

The previous prime is 172897987. The next prime is 172897997. The reversal of 172897993 is 399798271.

172897993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 399798271 = 6563 ⋅60917.

It is a cyclic number.

It is not a de Polignac number, because 172897993 - 2¹⁷ = 172766921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172897997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1217521 + ... + 1217662.

It is an arithmetic number, because the mean of its divisors is an integer number (43833312).

Almost surely, 2^172897993 is an apocalyptic number.

It is an amenable number.

172897993 is a deficient number, since it is larger than the sum of its proper divisors (2435255).

172897993 is an equidigital number, since it uses as much as digits as its factorization.

172897993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2435254.

The product of its digits is 1714608, while the sum is 55.

The square root of 172897993 is about 13149.0681418875. The cubic root of 172897993 is about 557.0959279184.

The spelling of 172897993 in words is "one hundred seventy-two million, eight hundred ninety-seven thousand, nine hundred ninety-three".