638145 has 32 divisors (see below), whose sum is σ = 1180800. Its totient is φ = 326592.

The previous prime is 638123. The next prime is 638147. The reversal of 638145 is 541836.

638145 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 638145 - 2⁶ = 638081 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an alternating number because its digits alternate between even and odd.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 638145.

It is not an unprimeable number, because it can be changed into a prime (638147) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3834 + ... + 3996.

It is an arithmetic number, because the mean of its divisors is an integer number (36900).

2⁶³⁸¹⁴⁵ is an apocalyptic number.

It is an amenable number.

638145 is a deficient number, since it is larger than the sum of its proper divisors (542655).

638145 is a wasteful number, since it uses less digits than its factorization.

638145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206 (or 200 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 638145 is about 798.8397836863. The cubic root of 638145 is about 86.0940471063.

The spelling of 638145 in words is "six hundred thirty-eight thousand, one hundred forty-five".