123428638 has 4 divisors (see below), whose sum is σ = 185142960. Its totient is φ = 61714318.

The previous prime is 123428629. The next prime is 123428647. The reversal of 123428638 is 836824321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 836824321 = 4969 ⋅168409.

It is an interprime number because it is at equal distance from previous prime (123428629) and next prime (123428647).

It is a junction number, because it is equal to n+sod(n) for n = 123428597 and 123428606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30857158 + ... + 30857161.

It is an arithmetic number, because the mean of its divisors is an integer number (46285740).

Almost surely, 2^123428638 is an apocalyptic number.

123428638 is a deficient number, since it is larger than the sum of its proper divisors (61714322).

123428638 is an equidigital number, since it uses as much as digits as its factorization.

123428638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61714321.

The product of its digits is 55296, while the sum is 37.

The square root of 123428638 is about 11109.8441933269. The cubic root of 123428638 is about 497.8960095334.

The spelling of 123428638 in words is "one hundred twenty-three million, four hundred twenty-eight thousand, six hundred thirty-eight".