638040974 has 16 divisors (see below), whose sum is σ = 1023811488. Its totient is φ = 297157632.

The previous prime is 638040973. The next prime is 638040979. The reversal of 638040974 is 479040836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638040973) 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, 93434 + ... + 100029.

It is an arithmetic number, because the mean of its divisors is an integer number (63988218).

Almost surely, 2^638040974 is an apocalyptic number.

638040974 is a deficient number, since it is larger than the sum of its proper divisors (385770514).

638040974 is a wasteful number, since it uses less digits than its factorization.

638040974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193579.

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 638040974 is about 25259.4729557052. The cubic root of 638040974 is about 860.8936869934.

The spelling of 638040974 in words is "six hundred thirty-eight million, forty thousand, nine hundred seventy-four".