28491949 has 8 divisors (see below), whose sum is σ = 31208760. Its totient is φ = 25890816.

The previous prime is 28491937. The next prime is 28491959. The reversal of 28491949 is 94919482.

It can be written as a sum of positive squares in 4 ways, for example, as 11269449 + 17222500 = 3357^2 + 4150^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28491949 - 2¹³ = 28483757 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28491899 and 28491908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28491919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28404 + ... + 29389.

It is an arithmetic number, because the mean of its divisors is an integer number (3901095).

Almost surely, 2^28491949 is an apocalyptic number.

28491949 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

28491949 is a deficient number, since it is larger than the sum of its proper divisors (2716811).

28491949 is a wasteful number, since it uses less digits than its factorization.

28491949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57839.

The product of its digits is 186624, while the sum is 46.

The square root of 28491949 is about 5337.7850275184. The cubic root of 28491949 is about 305.4269716502.

The spelling of 28491949 in words is "twenty-eight million, four hundred ninety-one thousand, nine hundred forty-nine".