21535606 has 8 divisors (see below), whose sum is σ = 32323104. Its totient is φ = 10761240.

The previous prime is 21535601. The next prime is 21535621. The reversal of 21535606 is 60653512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21535601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4771 + ... + 8113.

It is an arithmetic number, because the mean of its divisors is an integer number (4040388).

Almost surely, 2^21535606 is an apocalyptic number.

21535606 is a deficient number, since it is larger than the sum of its proper divisors (10787498).

21535606 is a wasteful number, since it uses less digits than its factorization.

21535606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6566.

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 21535606 is about 4640.6471531458. The cubic root of 21535606 is about 278.2183041075.

The spelling of 21535606 in words is "twenty-one million, five hundred thirty-five thousand, six hundred six".