27780945 has 32 divisors (see below), whose sum is σ = 47278080. Its totient is φ = 13890240.

The previous prime is 27780911. The next prime is 27781001. The reversal of 27780945 is 54908772.

It is not a de Polignac number, because 27780945 - 2⁷ = 27780817 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 27780897 and 27780906.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30040 + ... + 30950.

It is an arithmetic number, because the mean of its divisors is an integer number (1477440).

Almost surely, 2^27780945 is an apocalyptic number.

It is an amenable number.

27780945 is a deficient number, since it is larger than the sum of its proper divisors (19497135).

27780945 is a wasteful number, since it uses less digits than its factorization.

27780945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1045.

The product of its (nonzero) digits is 141120, while the sum is 42.

The square root of 27780945 is about 5270.7632274653. The cubic root of 27780945 is about 302.8649421507.

The spelling of 27780945 in words is "twenty-seven million, seven hundred eighty thousand, nine hundred forty-five".