28505501 has 2 divisors, whose sum is σ = 28505502. Its totient is φ = 28505500.

The previous prime is 28505471. The next prime is 28505507. The reversal of 28505501 is 10550582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25512601 + 2992900 = 5051^2 + 1730^2 .

It is a cyclic number.

It is not a de Polignac number, because 28505501 - 2¹⁸ = 28243357 is a prime.

It is a super-2 number, since 2×28505501² = 1625127174522002, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28505507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14252750 + 14252751.

It is an arithmetic number, because the mean of its divisors is an integer number (14252751).

Almost surely, 2^28505501 is an apocalyptic number.

It is an amenable number.

28505501 is a deficient number, since it is larger than the sum of its proper divisors (1).

28505501 is an equidigital number, since it uses as much as digits as its factorization.

28505501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2000, while the sum is 26.

The square root of 28505501 is about 5339.0543170116. The cubic root of 28505501 is about 305.4753887222.

The spelling of 28505501 in words is "twenty-eight million, five hundred five thousand, five hundred one".