28981969 has 2 divisors, whose sum is σ = 28981970. Its totient is φ = 28981968.

The previous prime is 28981943. The next prime is 28981999. The reversal of 28981969 is 96918982.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18386944 + 10595025 = 4288^2 + 3255^2 .

It is a cyclic number.

It is not a de Polignac number, because 28981969 - 2⁹ = 28981457 is a prime.

It is a super-2 number, since 2×28981969² = 1679909054233922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28981999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14490984 + 14490985.

It is an arithmetic number, because the mean of its divisors is an integer number (14490985).

Almost surely, 2^28981969 is an apocalyptic number.

It is an amenable number.

28981969 is a deficient number, since it is larger than the sum of its proper divisors (1).

28981969 is an equidigital number, since it uses as much as digits as its factorization.

28981969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 559872, while the sum is 52.

The square root of 28981969 is about 5383.4904105051. The cubic root of 28981969 is about 307.1679947182.

The spelling of 28981969 in words is "twenty-eight million, nine hundred eighty-one thousand, nine hundred sixty-nine".