27721747 has 6 divisors (see below), whose sum is σ = 29448668. Its totient is φ = 26090784.

The previous prime is 27721721. The next prime is 27721753. The reversal of 27721747 is 74712772.

It is not a de Polignac number, because 27721747 - 2⁷ = 27721619 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27721777) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 47673 + ... + 48250.

Almost surely, 2^27721747 is an apocalyptic number.

27721747 is a deficient number, since it is larger than the sum of its proper divisors (1726921).

27721747 is an equidigital number, since it uses as much as digits as its factorization.

27721747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95957 (or 95940 counting only the distinct ones).

The product of its digits is 38416, while the sum is 37.

The square root of 27721747 is about 5265.1445374272. The cubic root of 27721747 is about 302.6496657107.

Subtracting 27721747 from its reverse (74712772), we obtain a square (46991025 = 6855²).

The spelling of 27721747 in words is "twenty-seven million, seven hundred twenty-one thousand, seven hundred forty-seven".