28491623 has 2 divisors, whose sum is σ = 28491624. Its totient is φ = 28491622.

The previous prime is 28491611. The next prime is 28491629. The reversal of 28491623 is 32619482.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28491623 - 2⁸ = 28491367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28491629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14245811 + 14245812.

It is an arithmetic number, because the mean of its divisors is an integer number (14245812).

Almost surely, 2^28491623 is an apocalyptic number.

28491623 is a deficient number, since it is larger than the sum of its proper divisors (1).

28491623 is an equidigital number, since it uses as much as digits as its factorization.

28491623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20736, while the sum is 35.

The square root of 28491623 is about 5337.7544904201. The cubic root of 28491623 is about 305.4258067647.

The spelling of 28491623 in words is "twenty-eight million, four hundred ninety-one thousand, six hundred twenty-three".