638405828033 has 2 divisors, whose sum is σ = 638405828034. Its totient is φ = 638405828032.

The previous prime is 638405828023. The next prime is 638405828101. The reversal of 638405828033 is 330828504836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 379841713969 + 258564114064 = 616313^2 + 508492^2 .

It is a cyclic number.

It is not a de Polignac number, because 638405828033 - 2¹⁴ = 638405811649 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (638405828023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319202914016 + 319202914017.

It is an arithmetic number, because the mean of its divisors is an integer number (319202914017).

Almost surely, 2^638405828033 is an apocalyptic number.

It is an amenable number.

638405828033 is a deficient number, since it is larger than the sum of its proper divisors (1).

638405828033 is an equidigital number, since it uses as much as digits as its factorization.

638405828033 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3317760, while the sum is 50.

The spelling of 638405828033 in words is "six hundred thirty-eight billion, four hundred five million, eight hundred twenty-eight thousand, thirty-three".