21016716 has 24 divisors (see below), whose sum is σ = 56044800. Its totient is φ = 6004752.

The previous prime is 21016693. The next prime is 21016739. The reversal of 21016716 is 61761012.

It is an interprime number because it is at equal distance from previous prime (21016693) and next prime (21016739).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 125016 + ... + 125183.

It is an arithmetic number, because the mean of its divisors is an integer number (2335200).

Almost surely, 2^21016716 is an apocalyptic number.

It is an amenable number.

21016716 is an abundant number, since it is smaller than the sum of its proper divisors (35028084).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21016716 is a wasteful number, since it uses less digits than its factorization.

21016716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250213 (or 250211 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 21016716 is about 4584.3991972777. The cubic root of 21016716 is about 275.9656016782.

Adding to 21016716 its reverse (61761012), we get a palindrome (82777728).

The spelling of 21016716 in words is "twenty-one million, sixteen thousand, seven hundred sixteen".