21000527 has 2 divisors, whose sum is σ = 21000528. Its totient is φ = 21000526.

The previous prime is 21000517. The next prime is 21000533. The reversal of 21000527 is 72500012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21000527 - 2¹² = 20996431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000517) 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, 10500263 + 10500264.

It is an arithmetic number, because the mean of its divisors is an integer number (10500264).

Almost surely, 2^21000527 is an apocalyptic number.

21000527 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000527 is an equidigital number, since it uses as much as digits as its factorization.

21000527 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 140, while the sum is 17.

The square root of 21000527 is about 4582.6331950092. The cubic root of 21000527 is about 275.8947254808.

Adding to 21000527 its reverse (72500012), we get a palindrome (93500539).

The spelling of 21000527 in words is "twenty-one million, five hundred twenty-seven", and thus it is an aban number.