638634626782 has 16 divisors (see below), whose sum is σ = 1008466255440. Its totient is φ = 302482401408.

The previous prime is 638634626737. The next prime is 638634626789. The reversal of 638634626782 is 287626436836.

It is a self number, because there is not a number n which added to its sum of digits gives 638634626782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638634626789) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 390283 + ... + 1195654.

It is an arithmetic number, because the mean of its divisors is an integer number (63029140965).

Almost surely, 2^638634626782 is an apocalyptic number.

638634626782 is a deficient number, since it is larger than the sum of its proper divisors (369831628658).

638634626782 is a wasteful number, since it uses less digits than its factorization.

638634626782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1596555.

The product of its digits is 83607552, while the sum is 61.

The spelling of 638634626782 in words is "six hundred thirty-eight billion, six hundred thirty-four million, six hundred twenty-six thousand, seven hundred eighty-two".