21017122 has 8 divisors (see below), whose sum is σ = 36029376. Its totient is φ = 9007332.

The previous prime is 21017111. The next prime is 21017137. The reversal of 21017122 is 22171012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21017096 and 21017105.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 750598 + ... + 750625.

It is an arithmetic number, because the mean of its divisors is an integer number (4503672).

Almost surely, 2^21017122 is an apocalyptic number.

21017122 is a deficient number, since it is larger than the sum of its proper divisors (15012254).

21017122 is a wasteful number, since it uses less digits than its factorization.

21017122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1501232.

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 21017122 is about 4584.4434776753. The cubic root of 21017122 is about 275.9673786972.

Adding to 21017122 its reverse (22171012), we get a palindrome (43188134).

The spelling of 21017122 in words is "twenty-one million, seventeen thousand, one hundred twenty-two".