28121492 has 18 divisors (see below), whose sum is σ = 57247722. Its totient is φ = 12051984.

The previous prime is 28121491. The next prime is 28121497. The reversal of 28121492 is 29412182.

It can be written as a sum of positive squares in only one way, i.e., 15476356 + 12645136 = 3934^2 + 3556^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28121491) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 71543 + ... + 71934.

It is an arithmetic number, because the mean of its divisors is an integer number (3180429).

Almost surely, 2^28121492 is an apocalyptic number.

It is an amenable number.

28121492 is an abundant number, since it is smaller than the sum of its proper divisors (29126230).

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

28121492 is a wasteful number, since it uses less digits than its factorization.

28121492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143495 (or 143486 counting only the distinct ones).

The product of its digits is 2304, while the sum is 29.

The square root of 28121492 is about 5302.9701111735. The cubic root of 28121492 is about 304.0974554813.

The spelling of 28121492 in words is "twenty-eight million, one hundred twenty-one thousand, four hundred ninety-two".