638787145 has 8 divisors (see below), whose sum is σ = 784371456. Its totient is φ = 499145136.

The previous prime is 638787139. The next prime is 638787167. The reversal of 638787145 is 541787836.

It is a happy number.

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 638787145 - 2³ = 638787137 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1485337 + ... + 1485766.

It is an arithmetic number, because the mean of its divisors is an integer number (98046432).

Almost surely, 2^638787145 is an apocalyptic number.

It is an amenable number.

638787145 is a deficient number, since it is larger than the sum of its proper divisors (145584311).

638787145 is a wasteful number, since it uses less digits than its factorization.

638787145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2971151.

The product of its digits is 1128960, while the sum is 49.

The square root of 638787145 is about 25274.2387620280. The cubic root of 638787145 is about 861.2291532510.

The spelling of 638787145 in words is "six hundred thirty-eight million, seven hundred eighty-seven thousand, one hundred forty-five".