638426841 has 32 divisors (see below), whose sum is σ = 930951168. Its totient is φ = 386830080.

The previous prime is 638426837. The next prime is 638426863. The reversal of 638426841 is 148624836.

It is not a de Polignac number, because 638426841 - 2² = 638426837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 638426793 and 638426802.

It is not an unprimeable number, because it can be changed into a prime (638426881) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 777211 + ... + 778031.

It is an arithmetic number, because the mean of its divisors is an integer number (29092224).

Almost surely, 2^638426841 is an apocalyptic number.

It is an amenable number.

638426841 is a deficient number, since it is larger than the sum of its proper divisors (292524327).

638426841 is a wasteful number, since it uses less digits than its factorization.

638426841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1121.

The product of its digits is 221184, while the sum is 42.

The square root of 638426841 is about 25267.1098663856. The cubic root of 638426841 is about 861.0671991106.

The spelling of 638426841 in words is "six hundred thirty-eight million, four hundred twenty-six thousand, eight hundred forty-one".