21017214 has 12 divisors (see below), whose sum is σ = 45537336. Its totient is φ = 7005732.

The previous prime is 21017201. The next prime is 21017231. The reversal of 21017214 is 41271012.

It is a Harshad number since it is a multiple of its sum of digits (18), and also a Moran number because the ratio is a prime number: 1167623 = 21017214 / (2 + 1 + 0 + 1 + 7 + 2 + 1 + 4).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 583794 + ... + 583829.

It is an arithmetic number, because the mean of its divisors is an integer number (3794778).

Almost surely, 2^21017214 is an apocalyptic number.

21017214 is an abundant number, since it is smaller than the sum of its proper divisors (24520122).

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

21017214 is a wasteful number, since it uses less digits than its factorization.

21017214 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1167631 (or 1167628 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 21017214 is about 4584.4535115976. The cubic root of 21017214 is about 275.9677813683.

Adding to 21017214 its reverse (41271012), we get a palindrome (62288226).

It can be divided in two parts, 210 and 17214, that added together give a square (17424 = 132²).

The spelling of 21017214 in words is "twenty-one million, seventeen thousand, two hundred fourteen".