27960721 has 4 divisors (see below), whose sum is σ = 28008000. Its totient is φ = 27913444.

The previous prime is 27960719. The next prime is 27960731. The reversal of 27960721 is 12706972.

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 27960721 - 2¹ = 27960719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27960731) 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, 22741 + ... + 23938.

It is an arithmetic number, because the mean of its divisors is an integer number (7002000).

Almost surely, 2^27960721 is an apocalyptic number.

It is an amenable number.

27960721 is a deficient number, since it is larger than the sum of its proper divisors (47279).

27960721 is an equidigital number, since it uses as much as digits as its factorization.

27960721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47278.

The product of its (nonzero) digits is 10584, while the sum is 34.

The square root of 27960721 is about 5287.7898029328. The cubic root of 27960721 is about 303.5168376695.

The spelling of 27960721 in words is "twenty-seven million, nine hundred sixty thousand, seven hundred twenty-one".