21022604 has 6 divisors (see below), whose sum is σ = 36789564. Its totient is φ = 10511300.

The previous prime is 21022597. The next prime is 21022669. The reversal of 21022604 is 40622012.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2627822 + ... + 2627829.

It is an arithmetic number, because the mean of its divisors is an integer number (6131594).

Almost surely, 2^21022604 is an apocalyptic number.

It is an amenable number.

21022604 is a deficient number, since it is larger than the sum of its proper divisors (15766960).

21022604 is a wasteful number, since it uses less digits than its factorization.

21022604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5255655 (or 5255653 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21022604 is about 4585.0413302390. The cubic root of 21022604 is about 275.9913705907.

Adding to 21022604 its reverse (40622012), we get a palindrome (61644616).

The spelling of 21022604 in words is "twenty-one million, twenty-two thousand, six hundred four".