28071638 has 16 divisors (see below), whose sum is σ = 50215680. Its totient is φ = 11507496.

The previous prime is 28071613. The next prime is 28071653. The reversal of 28071638 is 83617082.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28071598 and 28071607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43268 + ... + 43911.

It is an arithmetic number, because the mean of its divisors is an integer number (3138480).

Almost surely, 2^28071638 is an apocalyptic number.

28071638 is a deficient number, since it is larger than the sum of its proper divisors (22144042).

28071638 is a wasteful number, since it uses less digits than its factorization.

28071638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87211.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 28071638 is about 5298.2674526679. The cubic root of 28071638 is about 303.9176470718.

The spelling of 28071638 in words is "twenty-eight million, seventy-one thousand, six hundred thirty-eight".