21516339 has 48 divisors (see below), whose sum is σ = 34659072. Its totient is φ = 11776512.

The previous prime is 21516311. The next prime is 21516359. The reversal of 21516339 is 93361512.

It is not a de Polignac number, because 21516339 - 2⁵ = 21516307 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21516359) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 259192 + ... + 259274.

It is an arithmetic number, because the mean of its divisors is an integer number (722064).

Almost surely, 2^21516339 is an apocalyptic number.

21516339 is a deficient number, since it is larger than the sum of its proper divisors (13142733).

21516339 is a wasteful number, since it uses less digits than its factorization.

21516339 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156 (or 139 counting only the distinct ones).

The product of its digits is 4860, while the sum is 30.

The square root of 21516339 is about 4638.5707928197. The cubic root of 21516339 is about 278.1353092841.

The spelling of 21516339 in words is "twenty-one million, five hundred sixteen thousand, three hundred thirty-nine".