643245513555 has 16 divisors (see below), whose sum is σ = 1029781983744. Its totient is φ = 342867886560.

The previous prime is 643245513541. The next prime is 643245513571. The reversal of 643245513555 is 555315542346.

It is not a de Polignac number, because 643245513555 - 2¹³ = 643245505363 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12247131 + ... + 12299540.

It is an arithmetic number, because the mean of its divisors is an integer number (64361373984).

Almost surely, 2^643245513555 is an apocalyptic number.

643245513555 is a deficient number, since it is larger than the sum of its proper divisors (386536470189).

643245513555 is a wasteful number, since it uses less digits than its factorization.

643245513555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24548426.

The product of its digits is 5400000, while the sum is 48.

The spelling of 643245513555 in words is "six hundred forty-three billion, two hundred forty-five million, five hundred thirteen thousand, five hundred fifty-five".