638457 has 16 divisors (see below), whose sum is σ = 936960. Its totient is φ = 384912.

The previous prime is 638453. The next prime is 638459. The reversal of 638457 is 754836.

It is not a de Polignac number, because 638457 - 2² = 638453 is a prime.

638457 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (638453) 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, 1068 + ... + 1554.

It is an arithmetic number, because the mean of its divisors is an integer number (58560).

2⁶³⁸⁴⁵⁷ is an apocalyptic number.

It is an amenable number.

638457 is a deficient number, since it is larger than the sum of its proper divisors (298503).

638457 is a wasteful number, since it uses less digits than its factorization.

638457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532.

The product of its digits is 20160, while the sum is 33.

The square root of 638457 is about 799.0350430363. The cubic root of 638457 is about 86.1080757708.

It can be divided in two parts, 6384 and 57, that added together give a triangular number (6441 = T₁₁₃).

The spelling of 638457 in words is "six hundred thirty-eight thousand, four hundred fifty-seven".