21601075 has 12 divisors (see below), whose sum is σ = 27034480. Its totient is φ = 17120160.

The previous prime is 21601061. The next prime is 21601121. The reversal of 21601075 is 57010612.

It is not a de Polignac number, because 21601075 - 2¹⁵ = 21568307 is a prime.

It is a zygodrome in base 3.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 1239 + ... + 6688.

Almost surely, 2^21601075 is an apocalyptic number.

21601075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21601075 is a deficient number, since it is larger than the sum of its proper divisors (5433405).

21601075 is a wasteful number, since it uses less digits than its factorization.

21601075 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8046 (or 8041 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 22.

The square root of 21601075 is about 4647.6956655960. The cubic root of 21601075 is about 278.4999500401.

Adding to 21601075 its reverse (57010612), we get a palindrome (78611687).

The spelling of 21601075 in words is "twenty-one million, six hundred one thousand, seventy-five".