28151929 has 4 divisors (see below), whose sum is σ = 30317476. Its totient is φ = 25986384.

The previous prime is 28151899. The next prime is 28151941. The reversal of 28151929 is 92915182.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2396304 + 25755625 = 1548^2 + 5075^2 .

It is a cyclic number.

It is not a de Polignac number, because 28151929 - 2⁷ = 28151801 is a prime.

It is a super-2 number, since 2×28151929² = 1585062212842082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28151029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1082754 + ... + 1082779.

It is an arithmetic number, because the mean of its divisors is an integer number (7579369).

Almost surely, 2^28151929 is an apocalyptic number.

It is an amenable number.

28151929 is a deficient number, since it is larger than the sum of its proper divisors (2165547).

28151929 is a wasteful number, since it uses less digits than its factorization.

28151929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2165546.

The product of its digits is 12960, while the sum is 37.

The square root of 28151929 is about 5305.8391419266. The cubic root of 28151929 is about 304.2071281467.

The spelling of 28151929 in words is "twenty-eight million, one hundred fifty-one thousand, nine hundred twenty-nine".