28901531 has 2 divisors, whose sum is σ = 28901532. Its totient is φ = 28901530.

The previous prime is 28901507. The next prime is 28901549. The reversal of 28901531 is 13510982.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28901531 - 2¹⁰ = 28900507 is a prime.

It is a super-2 number, since 2×28901531² = 1670596988287922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28901494 and 28901503.

It is not a weakly prime, because it can be changed into another prime (28901591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14450765 + 14450766.

It is an arithmetic number, because the mean of its divisors is an integer number (14450766).

Almost surely, 2^28901531 is an apocalyptic number.

28901531 is a deficient number, since it is larger than the sum of its proper divisors (1).

28901531 is an equidigital number, since it uses as much as digits as its factorization.

28901531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 28901531 is about 5376.0144159033. The cubic root of 28901531 is about 306.8835549566.

The spelling of 28901531 in words is "twenty-eight million, nine hundred one thousand, five hundred thirty-one".