645554643 has 8 divisors (see below), whose sum is σ = 874850256. Its totient is φ = 423314400.

The previous prime is 645554603. The next prime is 645554669. The reversal of 645554643 is 346455546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 645554643 - 2⁶ = 645554579 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 645554595 and 645554604.

It is not an unprimeable number, because it can be changed into a prime (645554603) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1763628 + ... + 1763993.

It is an arithmetic number, because the mean of its divisors is an integer number (109356282).

Almost surely, 2^645554643 is an apocalyptic number.

645554643 is a deficient number, since it is larger than the sum of its proper divisors (229295613).

645554643 is a wasteful number, since it uses less digits than its factorization.

645554643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3527685.

The product of its digits is 864000, while the sum is 42.

The square root of 645554643 is about 25407.7673753520. The cubic root of 645554643 is about 864.2598468800.

The spelling of 645554643 in words is "six hundred forty-five million, five hundred fifty-four thousand, six hundred forty-three".