645237167 has 4 divisors (see below), whose sum is σ = 647186856. Its totient is φ = 643287480.

The previous prime is 645237121. The next prime is 645237181. The reversal of 645237167 is 761732546.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 761732546 = 2 ⋅380866273.

It is a cyclic number.

It is not a de Polignac number, because 645237167 - 2²⁰ = 644188591 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 (645237107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 974348 + ... + 975009.

It is an arithmetic number, because the mean of its divisors is an integer number (161796714).

Almost surely, 2^645237167 is an apocalyptic number.

645237167 is a deficient number, since it is larger than the sum of its proper divisors (1949689).

645237167 is a wasteful number, since it uses less digits than its factorization.

645237167 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1949688.

The product of its digits is 211680, while the sum is 41.

The square root of 645237167 is about 25401.5189900132. The cubic root of 645237167 is about 864.1181461200.

The spelling of 645237167 in words is "six hundred forty-five million, two hundred thirty-seven thousand, one hundred sixty-seven".