21142061 has 2 divisors, whose sum is σ = 21142062. Its totient is φ = 21142060.

The previous prime is 21142021. The next prime is 21142087. The reversal of 21142061 is 16024112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19412836 + 1729225 = 4406^2 + 1315^2 .

It is a cyclic number.

It is not a de Polignac number, because 21142061 - 2¹⁰ = 21141037 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21142021) 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, 10571030 + 10571031.

It is an arithmetic number, because the mean of its divisors is an integer number (10571031).

Almost surely, 2^21142061 is an apocalyptic number.

It is an amenable number.

21142061 is a deficient number, since it is larger than the sum of its proper divisors (1).

21142061 is an equidigital number, since it uses as much as digits as its factorization.

21142061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 21142061 is about 4598.0496952512. The cubic root of 21142061 is about 276.5131399306.

Adding to 21142061 its reverse (16024112), we get a palindrome (37166173).

The spelling of 21142061 in words is "twenty-one million, one hundred forty-two thousand, sixty-one".