27945640 has 16 divisors (see below), whose sum is σ = 62877780. Its totient is φ = 11178240.

The previous prime is 27945629. The next prime is 27945649. The reversal of 27945640 is 4654972.

It can be written as a sum of positive squares in 2 ways, for example, as 27941796 + 3844 = 5286^2 + 62^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 27945640.

It is not an unprimeable number, because it can be changed into a prime (27945649) 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, 349281 + ... + 349360.

Almost surely, 2^27945640 is an apocalyptic number.

27945640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

27945640 is an abundant number, since it is smaller than the sum of its proper divisors (34932140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

27945640 is a wasteful number, since it uses less digits than its factorization.

27945640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698652 (or 698648 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 37.

The square root of 27945640 is about 5286.3635894630. The cubic root of 27945640 is about 303.4622591934.

The spelling of 27945640 in words is "twenty-seven million, nine hundred forty-five thousand, six hundred forty".