21016910 has 16 divisors (see below), whose sum is σ = 37887696. Its totient is φ = 8394048.

The previous prime is 21016903. The next prime is 21016949. The reversal of 21016910 is 1961012.

It is a Curzon number.

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, 8249 + ... + 10491.

It is an arithmetic number, because the mean of its divisors is an integer number (2367981).

Almost surely, 2^21016910 is an apocalyptic number.

21016910 is a deficient number, since it is larger than the sum of its proper divisors (16870786).

21016910 is a wasteful number, since it uses less digits than its factorization.

21016910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3187.

The product of its (nonzero) digits is 108, while the sum is 20.

The square root of 21016910 is about 4584.4203559447. The cubic root of 21016910 is about 275.9664507985.

Adding to 21016910 its reverse (1961012), we get a palindrome (22977922).

The spelling of 21016910 in words is "twenty-one million, sixteen thousand, nine hundred ten".