21470516 has 12 divisors (see below), whose sum is σ = 37752960. Its totient is φ = 10683960.

The previous prime is 21470509. The next prime is 21470521. The reversal of 21470516 is 61507412.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 11876 + ... + 13563.

It is an arithmetic number, because the mean of its divisors is an integer number (3146080).

Almost surely, 2^21470516 is an apocalyptic number.

It is an amenable number.

21470516 is a deficient number, since it is larger than the sum of its proper divisors (16282444).

21470516 is a wasteful number, since it uses less digits than its factorization.

21470516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25654 (or 25652 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 21470516 is about 4633.6288155181. The cubic root of 21470516 is about 277.9377221915.

Adding to 21470516 its reverse (61507412), we get a palindrome (82977928).

The spelling of 21470516 in words is "twenty-one million, four hundred seventy thousand, five hundred sixteen".