21006274 has 16 divisors (see below), whose sum is σ = 32934528. Its totient is φ = 10038672.

The previous prime is 21006263. The next prime is 21006277. The reversal of 21006274 is 47260012.

It is not an unprimeable number, because it can be changed into a prime (21006277) 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, 1444 + ... + 6640.

It is an arithmetic number, because the mean of its divisors is an integer number (2058408).

Almost surely, 2^21006274 is an apocalyptic number.

21006274 is a deficient number, since it is larger than the sum of its proper divisors (11928254).

21006274 is a wasteful number, since it uses less digits than its factorization.

21006274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5289.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 21006274 is about 4583.2601933558. The cubic root of 21006274 is about 275.9198902838.

Adding to 21006274 its reverse (47260012), we get a palindrome (68266286).

The spelling of 21006274 in words is "twenty-one million, six thousand, two hundred seventy-four".