638722543 has 8 divisors (see below), whose sum is σ = 660032640. Its totient is φ = 617456640.

The previous prime is 638722523. The next prime is 638722549. The reversal of 638722543 is 345227836.

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 638722543 - 2²¹ = 636625391 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 638722496 and 638722505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638722549) 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, 19743 + ... + 40831.

It is an arithmetic number, because the mean of its divisors is an integer number (82504080).

Almost surely, 2^638722543 is an apocalyptic number.

638722543 is a deficient number, since it is larger than the sum of its proper divisors (21310097).

638722543 is a wasteful number, since it uses less digits than its factorization.

638722543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22097.

The product of its digits is 241920, while the sum is 40.

The square root of 638722543 is about 25272.9607090266. The cubic root of 638722543 is about 861.2001195831.

The spelling of 638722543 in words is "six hundred thirty-eight million, seven hundred twenty-two thousand, five hundred forty-three".