21069061 has 6 divisors (see below), whose sum is σ = 22814610. Its totient is φ = 19448208.

The previous prime is 21069031. The next prime is 21069073. The reversal of 21069061 is 16096012.

21069061 is nontrivially palindromic in base 2.

It can be written as a sum of positive squares in 3 ways, for example, as 961 + 21068100 = 31^2 + 4590^2 .

It is not a de Polignac number, because 21069061 - 2¹³ = 21060869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21069031) 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 in 5 ways as a sum of consecutive naturals, for example, 62166 + ... + 62503.

It is an arithmetic number, because the mean of its divisors is an integer number (3802435).

Almost surely, 2^21069061 is an apocalyptic number.

It is an amenable number.

21069061 is a deficient number, since it is larger than the sum of its proper divisors (1745549).

21069061 is a wasteful number, since it uses less digits than its factorization.

21069061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124695 (or 124682 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 21069061 is about 4590.1046829021. The cubic root of 21069061 is about 276.1945217312.

The spelling of 21069061 in words is "twenty-one million, sixty-nine thousand, sixty-one".