28151604 has 48 divisors (see below), whose sum is σ = 78603840. Its totient is φ = 8661600.

The previous prime is 28151603. The next prime is 28151623. The reversal of 28151604 is 40615182.

28151604 is a `hidden beast` number, since 2 + 8 + 1 + 51 + 604 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28151603) 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, 8622 + ... + 11429.

It is an arithmetic number, because the mean of its divisors is an integer number (1637580).

Almost surely, 2^28151604 is an apocalyptic number.

It is an amenable number.

28151604 is an abundant number, since it is smaller than the sum of its proper divisors (50452236).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28151604 is a wasteful number, since it uses less digits than its factorization.

28151604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20077 (or 20069 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 28151604 is about 5305.8085152029. The cubic root of 28151604 is about 304.2059575023.

Adding to 28151604 its reverse (40615182), we get a palindrome (68766786).

The spelling of 28151604 in words is "twenty-eight million, one hundred fifty-one thousand, six hundred four".