27628381917 has 12 divisors (see below), whose sum is σ = 40014658684. Its totient is φ = 18369538560.

The previous prime is 27628381901. The next prime is 27628381969. The reversal of 27628381917 is 71918382672.

It is a happy number.

27628381917 is a `hidden beast` number, since 2 + 7 + 628 + 3 + 8 + 1 + 9 + 1 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 11023740036 + 16604641881 = 104994^2 + 128859^2 .

It is not a de Polignac number, because 27628381917 - 2⁴ = 27628381901 is a prime.

It is a super-2 number, since 2×27628381917² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27628381117) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4111684 + ... + 4118397.

Almost surely, 2^27628381917 is an apocalyptic number.

It is an amenable number.

27628381917 is a deficient number, since it is larger than the sum of its proper divisors (12386276767).

27628381917 is a wasteful number, since it uses less digits than its factorization.

27628381917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8230460 (or 8230457 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 54.

The spelling of 27628381917 in words is "twenty-seven billion, six hundred twenty-eight million, three hundred eighty-one thousand, nine hundred seventeen".