21516119 has 2 divisors, whose sum is σ = 21516120. Its totient is φ = 21516118.

The previous prime is 21516071. The next prime is 21516127. The reversal of 21516119 is 91161512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21516119 - 2²⁰ = 20467543 is a prime.

It is a super-2 number, since 2×21516119² = 925886753644322, which contains 22 as substring.

It is a Sophie Germain 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 (21516149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10758059 + 10758060.

It is an arithmetic number, because the mean of its divisors is an integer number (10758060).

Almost surely, 2^21516119 is an apocalyptic number.

21516119 is a deficient number, since it is larger than the sum of its proper divisors (1).

21516119 is an equidigital number, since it uses as much as digits as its factorization.

21516119 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 540, while the sum is 26.

The square root of 21516119 is about 4638.5470785581. The cubic root of 21516119 is about 278.1343613227.

The spelling of 21516119 in words is "twenty-one million, five hundred sixteen thousand, one hundred nineteen".