21120716 has 24 divisors (see below), whose sum is σ = 38967264. Its totient is φ = 9996800.

The previous prime is 21120713. The next prime is 21120721. The reversal of 21120716 is 61702112.

It is not an unprimeable number, because it can be changed into a prime (21120713) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8156 + ... + 10428.

It is an arithmetic number, because the mean of its divisors is an integer number (1623636).

Almost surely, 2^21120716 is an apocalyptic number.

It is an amenable number.

21120716 is a deficient number, since it is larger than the sum of its proper divisors (17846548).

21120716 is a wasteful number, since it uses less digits than its factorization.

21120716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2401 (or 2399 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 20.

The square root of 21120716 is about 4595.7280163212. The cubic root of 21120716 is about 276.4200528161.

Adding to 21120716 its reverse (61702112), we get a palindrome (82822828).

The spelling of 21120716 in words is "twenty-one million, one hundred twenty thousand, seven hundred sixteen".