28155879 has 24 divisors (see below), whose sum is σ = 42103152. Its totient is φ = 18120960.

The previous prime is 28155877. The next prime is 28155901. The reversal of 28155879 is 97855182.

It is a happy number.

28155879 is a `hidden beast` number, since 28 + 1 + 558 + 79 = 666.

It is not a de Polignac number, because 28155879 - 2¹ = 28155877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28155877) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31519 + ... + 32399.

It is an arithmetic number, because the mean of its divisors is an integer number (1754298).

Almost surely, 2^28155879 is an apocalyptic number.

28155879 is a deficient number, since it is larger than the sum of its proper divisors (13947273).

28155879 is a wasteful number, since it uses less digits than its factorization.

28155879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1007 (or 1004 counting only the distinct ones).

The product of its digits is 201600, while the sum is 45.

The square root of 28155879 is about 5306.2113602833. The cubic root of 28155879 is about 304.2213552590.

The spelling of 28155879 in words is "twenty-eight million, one hundred fifty-five thousand, eight hundred seventy-nine".