21225607 has 12 divisors (see below), whose sum is σ = 23633400. Its totient is φ = 18949680.

The previous prime is 21225583. The next prime is 21225613. The reversal of 21225607 is 70652212.

It is not a de Polignac number, because 21225607 - 2¹⁵ = 21192839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21205607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11644 + ... + 13342.

It is an arithmetic number, because the mean of its divisors is an integer number (1969450).

Almost surely, 2^21225607 is an apocalyptic number.

21225607 is a deficient number, since it is larger than the sum of its proper divisors (2407793).

21225607 is a wasteful number, since it uses less digits than its factorization.

21225607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1774 (or 1743 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 21225607 is about 4607.1256766014. The cubic root of 21225607 is about 276.8768888205.

Adding to 21225607 its reverse (70652212), we get a palindrome (91877819).

The spelling of 21225607 in words is "twenty-one million, two hundred twenty-five thousand, six hundred seven".