638011061 has 2 divisors, whose sum is σ = 638011062. Its totient is φ = 638011060.

The previous prime is 638010949. The next prime is 638011069. The reversal of 638011061 is 160110836.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 350064100 + 287946961 = 18710^2 + 16969^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638011061 is a prime.

It is a super-2 number, since 2×638011061² = 814116227916691442, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 638011061.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638011069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319005530 + 319005531.

It is an arithmetic number, because the mean of its divisors is an integer number (319005531).

Almost surely, 2^638011061 is an apocalyptic number.

It is an amenable number.

638011061 is a deficient number, since it is larger than the sum of its proper divisors (1).

638011061 is an equidigital number, since it uses as much as digits as its factorization.

638011061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 638011061 is about 25258.8808342729. The cubic root of 638011061 is about 860.8802331473.

Adding to 638011061 its reverse (160110836), we get a palindrome (798121897).

The spelling of 638011061 in words is "six hundred thirty-eight million, eleven thousand, sixty-one".