644142250136356 has 12 divisors (see below), whose sum is σ = 1137224592055692. Its totient is φ = 319220938120448.

The previous prime is 644142250136327. The next prime is 644142250136401. The reversal of 644142250136356 is 653631052241446.

It can be written as a sum of positive squares in 2 ways, for example, as 264193816321600 + 379948433814756 = 16254040^2 + 19492266^2 .

It is an unprimeable number.

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, 712546736425 + ... + 712546737328.

It is an arithmetic number, because the mean of its divisors is an integer number (94768716004641).

Almost surely, 2^{644142250136356} is an apocalyptic number.

It is an amenable number.

644142250136356 is a deficient number, since it is larger than the sum of its proper divisors (493082341919336).

644142250136356 is a wasteful number, since it uses less digits than its factorization.

644142250136356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1425093473870 (or 1425093473868 counting only the distinct ones).

The product of its (nonzero) digits is 12441600, while the sum is 52.

The spelling of 644142250136356 in words is "six hundred forty-four trillion, one hundred forty-two billion, two hundred fifty million, one hundred thirty-six thousand, three hundred fifty-six".