645424141 has 4 divisors (see below), whose sum is σ = 647252892. Its totient is φ = 643595392.

The previous prime is 645424139. The next prime is 645424177. The reversal of 645424141 is 141424546.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 141424546 = 2 ⋅70712273.

It can be written as a sum of positive squares in 2 ways, for example, as 437228100 + 208196041 = 20910^2 + 14429^2 .

It is a cyclic number.

It is not a de Polignac number, because 645424141 - 2¹ = 645424139 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 (645421141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 913846 + ... + 914551.

It is an arithmetic number, because the mean of its divisors is an integer number (161813223).

Almost surely, 2^645424141 is an apocalyptic number.

It is an amenable number.

645424141 is a deficient number, since it is larger than the sum of its proper divisors (1828751).

645424141 is a wasteful number, since it uses less digits than its factorization.

645424141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1828750.

The product of its digits is 15360, while the sum is 31.

The square root of 645424141 is about 25405.1990938863. The cubic root of 645424141 is about 864.2016048495.

Adding to 645424141 its reverse (141424546), we get a palindrome (786848687).

The spelling of 645424141 in words is "six hundred forty-five million, four hundred twenty-four thousand, one hundred forty-one".