638762011 has 2 divisors, whose sum is σ = 638762012. Its totient is φ = 638762010.

The previous prime is 638762009. The next prime is 638762021. The reversal of 638762011 is 110267836.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 638762011 - 2¹ = 638762009 is a prime.

Together with 638762009, it forms a pair of twin primes.

It is equal to p_33239437 and since 638762011 and 33239437 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (638762021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319381005 + 319381006.

It is an arithmetic number, because the mean of its divisors is an integer number (319381006).

Almost surely, 2^638762011 is an apocalyptic number.

638762011 is a deficient number, since it is larger than the sum of its proper divisors (1).

638762011 is an equidigital number, since it uses as much as digits as its factorization.

638762011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 638762011 is about 25273.7415314789. The cubic root of 638762011 is about 861.2178576691.

The spelling of 638762011 in words is "six hundred thirty-eight million, seven hundred sixty-two thousand, eleven".