172887997 has 4 divisors (see below), whose sum is σ = 172920160. Its totient is φ = 172855836.

The previous prime is 172887983. The next prime is 172888003. The reversal of 172887997 is 799788271.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172887997 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 (172887917) 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, 5847 + ... + 19492.

It is an arithmetic number, because the mean of its divisors is an integer number (43230040).

Almost surely, 2^172887997 is an apocalyptic number.

It is an amenable number.

172887997 is a deficient number, since it is larger than the sum of its proper divisors (32163).

172887997 is an equidigital number, since it uses as much as digits as its factorization.

172887997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32162.

The product of its digits is 3556224, while the sum is 58.

The square root of 172887997 is about 13148.6880334123. The cubic root of 172887997 is about 557.0851916492.

The spelling of 172887997 in words is "one hundred seventy-two million, eight hundred eighty-seven thousand, nine hundred ninety-seven".