28978961 has 8 divisors (see below), whose sum is σ = 31653504. Its totient is φ = 26311120.

The previous prime is 28978949. The next prime is 28978973. The reversal of 28978961 is 16987982.

It is an interprime number because it is at equal distance from previous prime (28978949) and next prime (28978973).

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

It is not a de Polignac number, because 28978961 - 2¹⁰ = 28977937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28978981) 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 7 ways as a sum of consecutive naturals, for example, 13016 + ... + 15078.

It is an arithmetic number, because the mean of its divisors is an integer number (3956688).

Almost surely, 2^28978961 is an apocalyptic number.

It is an amenable number.

28978961 is a deficient number, since it is larger than the sum of its proper divisors (2674543).

28978961 is a wasteful number, since it uses less digits than its factorization.

28978961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3351.

The product of its digits is 435456, while the sum is 50.

The square root of 28978961 is about 5383.2110306025. The cubic root of 28978961 is about 307.1573674981.

It can be divided in two parts, 289 and 78961, that multiplied together give a square (22819729 = 4777²).

The spelling of 28978961 in words is "twenty-eight million, nine hundred seventy-eight thousand, nine hundred sixty-one".