645311426205 has 64 divisors (see below), whose sum is σ = 1072191375360. Its totient is φ = 331028495616.

The previous prime is 645311426173. The next prime is 645311426231. The reversal of 645311426205 is 502624113546.

It is not a de Polignac number, because 645311426205 - 2⁵ = 645311426173 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 143177562 + ... + 143182068.

It is an arithmetic number, because the mean of its divisors is an integer number (16752990240).

Almost surely, 2^645311426205 is an apocalyptic number.

It is an amenable number.

645311426205 is a deficient number, since it is larger than the sum of its proper divisors (426879949155).

645311426205 is a wasteful number, since it uses less digits than its factorization.

645311426205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5730.

The product of its (nonzero) digits is 172800, while the sum is 39.

The spelling of 645311426205 in words is "six hundred forty-five billion, three hundred eleven million, four hundred twenty-six thousand, two hundred five".