21225410 has 16 divisors (see below), whose sum is σ = 38487096. Its totient is φ = 8427648.

The previous prime is 21225403. The next prime is 21225431. The reversal of 21225410 is 1452212.

It can be written as a sum of positive squares in 4 ways, for example, as 12327121 + 8898289 = 3511^2 + 2983^2 .

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, 6377 + ... + 9116.

Almost surely, 2^21225410 is an apocalyptic number.

21225410 is a deficient number, since it is larger than the sum of its proper divisors (17261686).

21225410 is a wasteful number, since it uses less digits than its factorization.

21225410 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15637.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 21225410 is about 4607.1042966271. The cubic root of 21225410 is about 276.8760322307.

Adding to 21225410 its reverse (1452212), we get a palindrome (22677622).

The spelling of 21225410 in words is "twenty-one million, two hundred twenty-five thousand, four hundred ten".