638817801 has 8 divisors (see below), whose sum is σ = 888790080. Its totient is φ = 407362032.

The previous prime is 638817799. The next prime is 638817821. The reversal of 638817801 is 108718836.

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

It is not a de Polignac number, because 638817801 - 2¹ = 638817799 is a prime.

It is not an unprimeable number, because it can be changed into a prime (638817821) 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, 4629046 + ... + 4629183.

It is an arithmetic number, because the mean of its divisors is an integer number (111098760).

Almost surely, 2^638817801 is an apocalyptic number.

It is an amenable number.

638817801 is a deficient number, since it is larger than the sum of its proper divisors (249972279).

638817801 is a wasteful number, since it uses less digits than its factorization.

638817801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9258255.

The product of its (nonzero) digits is 64512, while the sum is 42.

The square root of 638817801 is about 25274.8452220780. The cubic root of 638817801 is about 861.2429300981.

The spelling of 638817801 in words is "six hundred thirty-eight million, eight hundred seventeen thousand, eight hundred one".