21740016 has 40 divisors (see below), whose sum is σ = 57684304. Its totient is φ = 7050240.

The previous prime is 21740011. The next prime is 21740023. The reversal of 21740016 is 61004712.

It is a junction number, because it is equal to n+sod(n) for n = 21739974 and 21740001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21740011) 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, 4345 + ... + 7896.

Almost surely, 2^21740016 is an apocalyptic number.

It is an amenable number.

21740016 is an abundant number, since it is smaller than the sum of its proper divisors (35944288).

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

21740016 is a wasteful number, since it uses less digits than its factorization.

21740016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12289 (or 12283 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 21740016 is about 4662.6190065241. The cubic root of 21740016 is about 279.0957906456.

Adding to 21740016 its reverse (61004712), we get a palindrome (82744728).

The spelling of 21740016 in words is "twenty-one million, seven hundred forty thousand, sixteen".