28378837 has 4 divisors (see below), whose sum is σ = 29872480. Its totient is φ = 26885196.

The previous prime is 28378829. The next prime is 28378841. The reversal of 28378837 is 73887382.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 73887382 = 2 ⋅36943691.

It is a cyclic number.

It is not a de Polignac number, because 28378837 - 2³ = 28378829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28378817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 746793 + ... + 746830.

It is an arithmetic number, because the mean of its divisors is an integer number (7468120).

Almost surely, 2^28378837 is an apocalyptic number.

It is an amenable number.

28378837 is a deficient number, since it is larger than the sum of its proper divisors (1493643).

28378837 is a wasteful number, since it uses less digits than its factorization.

28378837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1493642.

The product of its digits is 451584, while the sum is 46.

The square root of 28378837 is about 5327.1790846563. The cubic root of 28378837 is about 305.0222576250.

The spelling of 28378837 in words is "twenty-eight million, three hundred seventy-eight thousand, eight hundred thirty-seven".