28552981 has 2 divisors, whose sum is σ = 28552982. Its totient is φ = 28552980.

The previous prime is 28552973. The next prime is 28552987. The reversal of 28552981 is 18925582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22648081 + 5904900 = 4759^2 + 2430^2 .

It is a cyclic number.

It is not a de Polignac number, because 28552981 - 2³ = 28552973 is a prime.

It is a super-2 number, since 2×28552981² = 1630545447972722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28552987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14276490 + 14276491.

It is an arithmetic number, because the mean of its divisors is an integer number (14276491).

Almost surely, 2^28552981 is an apocalyptic number.

It is an amenable number.

28552981 is a deficient number, since it is larger than the sum of its proper divisors (1).

28552981 is an equidigital number, since it uses as much as digits as its factorization.

28552981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57600, while the sum is 40.

The square root of 28552981 is about 5343.4989473191. The cubic root of 28552981 is about 305.6448989989.

The spelling of 28552981 in words is "twenty-eight million, five hundred fifty-two thousand, nine hundred eighty-one".