21010489 has 2 divisors, whose sum is σ = 21010490. Its totient is φ = 21010488.

The previous prime is 21010469. The next prime is 21010501. The reversal of 21010489 is 98401012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20548089 + 462400 = 4533^2 + 680^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010489 - 2⁷ = 21010361 is a prime.

It is not a weakly prime, because it can be changed into another prime (21010469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505244 + 10505245.

It is an arithmetic number, because the mean of its divisors is an integer number (10505245).

Almost surely, 2^21010489 is an apocalyptic number.

It is an amenable number.

21010489 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010489 is an equidigital number, since it uses as much as digits as its factorization.

21010489 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 21010489 is about 4583.7199958113. The cubic root of 21010489 is about 275.9383438905.

The spelling of 21010489 in words is "twenty-one million, ten thousand, four hundred eighty-nine".