638405508073 has 16 divisors (see below), whose sum is σ = 670357284480. Its totient is φ = 607118472576.

The previous prime is 638405507951. The next prime is 638405508079. The reversal of 638405508073 is 370805504836.

It is not a de Polignac number, because 638405508073 - 2¹³ = 638405499881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638405508079) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22977636 + ... + 23005402.

It is an arithmetic number, because the mean of its divisors is an integer number (41897330280).

Almost surely, 2^638405508073 is an apocalyptic number.

It is an amenable number.

638405508073 is a deficient number, since it is larger than the sum of its proper divisors (31951776407).

638405508073 is a wasteful number, since it uses less digits than its factorization.

638405508073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39696.

The product of its (nonzero) digits is 2419200, while the sum is 49.

The spelling of 638405508073 in words is "six hundred thirty-eight billion, four hundred five million, five hundred eight thousand, seventy-three".