638353461747 has 4 divisors (see below), whose sum is σ = 851137949000. Its totient is φ = 425568974496.

The previous prime is 638353461701. The next prime is 638353461787. The reversal of 638353461747 is 747164353836.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 638353461747 - 2¹⁹ = 638352937459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638353461787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106392243622 + ... + 106392243627.

It is an arithmetic number, because the mean of its divisors is an integer number (212784487250).

Almost surely, 2^638353461747 is an apocalyptic number.

638353461747 is a deficient number, since it is larger than the sum of its proper divisors (212784487253).

638353461747 is a wasteful number, since it uses less digits than its factorization.

638353461747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212784487252.

The product of its digits is 30481920, while the sum is 57.

The spelling of 638353461747 in words is "six hundred thirty-eight billion, three hundred fifty-three million, four hundred sixty-one thousand, seven hundred forty-seven".