27172021 has 4 divisors (see below), whose sum is σ = 27324000. Its totient is φ = 27020044.

The previous prime is 27172009. The next prime is 27172099. The reversal of 27172021 is 12027172.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27172021 - 2²¹ = 25074869 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 27171983 and 27172001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27172421) 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, 75721 + ... + 76078.

It is an arithmetic number, because the mean of its divisors is an integer number (6831000).

Almost surely, 2^27172021 is an apocalyptic number.

It is an amenable number.

27172021 is a deficient number, since it is larger than the sum of its proper divisors (151979).

27172021 is a wasteful number, since it uses less digits than its factorization.

27172021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151978.

The product of its (nonzero) digits is 392, while the sum is 22.

The square root of 27172021 is about 5212.6788698327. The cubic root of 27172021 is about 300.6357665328.

Adding to 27172021 its reverse (12027172), we get a palindrome (39199193).

The spelling of 27172021 in words is "twenty-seven million, one hundred seventy-two thousand, twenty-one".