27707021 has 4 divisors (see below), whose sum is σ = 28382844. Its totient is φ = 27031200.

The previous prime is 27706999. The next prime is 27707023. The reversal of 27707021 is 12070772.

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 978121 + 26728900 = 989^2 + 5170^2 .

It is a cyclic number.

It is not a de Polignac number, because 27707021 - 2¹⁸ = 27444877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27707023) 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, 337850 + ... + 337931.

It is an arithmetic number, because the mean of its divisors is an integer number (7095711).

Almost surely, 2^27707021 is an apocalyptic number.

It is an amenable number.

27707021 is a deficient number, since it is larger than the sum of its proper divisors (675823).

27707021 is an equidigital number, since it uses as much as digits as its factorization.

27707021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 675822.

The product of its (nonzero) digits is 1372, while the sum is 26.

The square root of 27707021 is about 5263.7459095211. The cubic root of 27707021 is about 302.5960662943.

Adding to 27707021 its reverse (12070772), we get a palindrome (39777793).

The spelling of 27707021 in words is "twenty-seven million, seven hundred seven thousand, twenty-one".