638323973 has 8 divisors (see below), whose sum is σ = 772425792. Its totient is φ = 514950336.

The previous prime is 638323937. The next prime is 638324021. The reversal of 638323973 is 379323836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 638323973 - 2⁶ = 638323909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638323913) 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, 2681915 + ... + 2682152.

It is an arithmetic number, because the mean of its divisors is an integer number (96553224).

Almost surely, 2^638323973 is an apocalyptic number.

It is an amenable number.

638323973 is a deficient number, since it is larger than the sum of its proper divisors (134101819).

638323973 is a wasteful number, since it uses less digits than its factorization.

638323973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5364091.

The product of its digits is 489888, while the sum is 44.

The square root of 638323973 is about 25265.0741736493. The cubic root of 638323973 is about 861.0209494791.

The spelling of 638323973 in words is "six hundred thirty-eight million, three hundred twenty-three thousand, nine hundred seventy-three".