642173167 has 2 divisors, whose sum is σ = 642173168. Its totient is φ = 642173166.

The previous prime is 642173131. The next prime is 642173171. The reversal of 642173167 is 761371246.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 642173167 - 2¹⁵ = 642140399 is a prime.

It is equal to p_33407659 and since 642173167 and 33407659 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642173107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321086583 + 321086584.

It is an arithmetic number, because the mean of its divisors is an integer number (321086584).

Almost surely, 2^642173167 is an apocalyptic number.

642173167 is a deficient number, since it is larger than the sum of its proper divisors (1).

642173167 is an equidigital number, since it uses as much as digits as its factorization.

642173167 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 37.

The square root of 642173167 is about 25341.1358664129. The cubic root of 642173167 is about 862.7481795646.

The spelling of 642173167 in words is "six hundred forty-two million, one hundred seventy-three thousand, one hundred sixty-seven".