21570104 has 16 divisors (see below), whose sum is σ = 40517520. Its totient is φ = 10765440.

The previous prime is 21570103. The next prime is 21570137. The reversal of 21570104 is 40107512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21570103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2912 + ... + 7184.

It is an arithmetic number, because the mean of its divisors is an integer number (2532345).

Almost surely, 2^21570104 is an apocalyptic number.

It is an amenable number.

21570104 is a deficient number, since it is larger than the sum of its proper divisors (18947416).

21570104 is a wasteful number, since it uses less digits than its factorization.

21570104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4910 (or 4906 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 21570104 is about 4644.3626042763. The cubic root of 21570104 is about 278.3667846377.

Adding to 21570104 its reverse (40107512), we get a palindrome (61677616).

The spelling of 21570104 in words is "twenty-one million, five hundred seventy thousand, one hundred four".