642644245 has 8 divisors (see below), whose sum is σ = 789107616. Its totient is φ = 502159056.

The previous prime is 642644243. The next prime is 642644269. The reversal of 642644245 is 542446246.

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

It is a cyclic number.

It is not a de Polignac number, because 642644245 - 2¹ = 642644243 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642644243) 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, 1494307 + ... + 1494736.

It is an arithmetic number, because the mean of its divisors is an integer number (98638452).

Almost surely, 2^642644245 is an apocalyptic number.

It is an amenable number.

642644245 is a deficient number, since it is larger than the sum of its proper divisors (146463371).

642644245 is a wasteful number, since it uses less digits than its factorization.

642644245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2989091.

The product of its digits is 184320, while the sum is 37.

The square root of 642644245 is about 25350.4288918353. The cubic root of 642644245 is about 862.9590896269.

The spelling of 642644245 in words is "six hundred forty-two million, six hundred forty-four thousand, two hundred forty-five".