642654173 has 4 divisors (see below), whose sum is σ = 734461920. Its totient is φ = 550846428.

The previous prime is 642654169. The next prime is 642654191. The reversal of 642654173 is 371456246.

It is a happy number.

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 not a de Polignac number, because 642654173 - 2² = 642654169 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 (642654193) 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, 45903863 + ... + 45903876.

It is an arithmetic number, because the mean of its divisors is an integer number (183615480).

Almost surely, 2^642654173 is an apocalyptic number.

It is an amenable number.

642654173 is a deficient number, since it is larger than the sum of its proper divisors (91807747).

642654173 is an equidigital number, since it uses as much as digits as its factorization.

642654173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91807746.

The product of its digits is 120960, while the sum is 38.

The square root of 642654173 is about 25350.6247063065. The cubic root of 642654173 is about 862.9635334612.

The spelling of 642654173 in words is "six hundred forty-two million, six hundred fifty-four thousand, one hundred seventy-three".