638189461 has 24 divisors (see below), whose sum is σ = 831376320. Its totient is φ = 478348416.

The previous prime is 638189459. The next prime is 638189479. The reversal of 638189461 is 164981836.

It is not a de Polignac number, because 638189461 - 2¹ = 638189459 is a prime.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638189411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8281 + ... + 36673.

It is an arithmetic number, because the mean of its divisors is an integer number (34640680).

Almost surely, 2^638189461 is an apocalyptic number.

It is an amenable number.

638189461 is a deficient number, since it is larger than the sum of its proper divisors (193186859).

638189461 is a wasteful number, since it uses less digits than its factorization.

638189461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28445 (or 28432 counting only the distinct ones).

The product of its digits is 248832, while the sum is 46.

The square root of 638189461 is about 25262.4120186494. The cubic root of 638189461 is about 860.9604651529.

The spelling of 638189461 in words is "six hundred thirty-eight million, one hundred eighty-nine thousand, four hundred sixty-one".