645024340 has 48 divisors (see below), whose sum is σ = 1372911120. Its totient is φ = 254535680.

The previous prime is 645024311. The next prime is 645024349. The reversal of 645024340 is 43420546.

It can be written as a sum of positive squares in 8 ways, for example, as 193376836 + 451647504 = 13906^2 + 21252^2 .

It is a junction number, because it is equal to n+sod(n) for n = 645024299 and 645024308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645024349) 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 15 ways as a sum of consecutive naturals, for example, 607410 + ... + 608470.

It is an arithmetic number, because the mean of its divisors is an integer number (28602315).

Almost surely, 2^645024340 is an apocalyptic number.

It is an amenable number.

645024340 is an abundant number, since it is smaller than the sum of its proper divisors (727886780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645024340 is a wasteful number, since it uses less digits than its factorization.

645024340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1452 (or 1450 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 28.

The square root of 645024340 is about 25397.3293871620. The cubic root of 645024340 is about 864.0231278817.

Adding to 645024340 its reverse (43420546), we get a palindrome (688444886).

The spelling of 645024340 in words is "six hundred forty-five million, twenty-four thousand, three hundred forty".