21207274 has 16 divisors (see below), whose sum is σ = 35194176. Its totient is φ = 9503200.

The previous prime is 21207271. The next prime is 21207301. The reversal of 21207274 is 47270212.

It is a super-2 number, since 2×21207274² = 899496941022152, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21207271) 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, 5227 + ... + 8350.

It is an arithmetic number, because the mean of its divisors is an integer number (2199636).

Almost surely, 2^21207274 is an apocalyptic number.

21207274 is a deficient number, since it is larger than the sum of its proper divisors (13986902).

21207274 is a wasteful number, since it uses less digits than its factorization.

21207274 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13661.

The product of its (nonzero) digits is 1568, while the sum is 25.

The square root of 21207274 is about 4605.1356114668. The cubic root of 21207274 is about 276.7971510755.

Adding to 21207274 its reverse (47270212), we get a palindrome (68477486).

The spelling of 21207274 in words is "twenty-one million, two hundred seven thousand, two hundred seventy-four".