21675545 has 8 divisors (see below), whose sum is σ = 27141696. Its totient is φ = 16586416.

The previous prime is 21675529. The next prime is 21675553. The reversal of 21675545 is 54557612.

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

It is a cyclic number.

It is not a de Polignac number, because 21675545 - 2⁴ = 21675529 is a prime.

It is a Duffinian number.

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 7 ways as a sum of consecutive naturals, for example, 94127 + ... + 94356.

It is an arithmetic number, because the mean of its divisors is an integer number (3392712).

Almost surely, 2^21675545 is an apocalyptic number.

It is an amenable number.

21675545 is a deficient number, since it is larger than the sum of its proper divisors (5466151).

21675545 is a wasteful number, since it uses less digits than its factorization.

21675545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188511.

The product of its digits is 42000, while the sum is 35.

The square root of 21675545 is about 4655.7002695620. The cubic root of 21675545 is about 278.8196270799.

The spelling of 21675545 in words is "twenty-one million, six hundred seventy-five thousand, five hundred forty-five".