645540587 has 2 divisors, whose sum is σ = 645540588. Its totient is φ = 645540586.

The previous prime is 645540481. The next prime is 645540593. The reversal of 645540587 is 785045546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645540587 - 2¹⁰ = 645539563 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (645540787) 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 as a sum of consecutive naturals, namely, 322770293 + 322770294.

It is an arithmetic number, because the mean of its divisors is an integer number (322770294).

Almost surely, 2^645540587 is an apocalyptic number.

645540587 is a deficient number, since it is larger than the sum of its proper divisors (1).

645540587 is an equidigital number, since it uses as much as digits as its factorization.

645540587 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672000, while the sum is 44.

The square root of 645540587 is about 25407.4907655203. The cubic root of 645540587 is about 864.2535741734.

The spelling of 645540587 in words is "six hundred forty-five million, five hundred forty thousand, five hundred eighty-seven".