27906121 has 4 divisors (see below), whose sum is σ = 27919044. Its totient is φ = 27893200.

The previous prime is 27906031. The next prime is 27906127. The reversal of 27906121 is 12160972.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12390400 + 15515721 = 3520^2 + 3939^2 .

It is a cyclic number.

It is not a de Polignac number, because 27906121 - 2¹¹ = 27904073 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 27906121.

It is not an unprimeable number, because it can be changed into a prime (27906127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2350 + ... + 7831.

It is an arithmetic number, because the mean of its divisors is an integer number (6979761).

Almost surely, 2^27906121 is an apocalyptic number.

It is an amenable number.

27906121 is a deficient number, since it is larger than the sum of its proper divisors (12923).

27906121 is a wasteful number, since it uses less digits than its factorization.

27906121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12922.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 27906121 is about 5282.6244424528. The cubic root of 27906121 is about 303.3191458432.

It can be divided in two parts, 2790 and 6121, that added together give a triangular number (8911 = T₁₃₃).

The spelling of 27906121 in words is "twenty-seven million, nine hundred six thousand, one hundred twenty-one".