27148778781601 has 27 divisors (see below), whose sum is σ = 29803043749107. Its totient is φ = 24725039430720.

The previous prime is 27148778781599. The next prime is 27148778781613. The reversal of 27148778781601 is 10618787784172.

The square root of 27148778781601 is 5210449.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 21136592477025 + 6012186304576 = 4597455^2 + 2451976^2 .

It is not a de Polignac number, because 27148778781601 - 2¹ = 27148778781599 is a prime.

It is a super-2 number, since 2×27148778781601² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27148778781401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2745901680 + ... + 2745911566.

Almost surely, 2^{27148778781601} is an apocalyptic number.

27148778781601 is the 5210449-th square number.

27148778781601 is the 2605225-th centered octagonal number.

It is an amenable number.

27148778781601 is a deficient number, since it is larger than the sum of its proper divisors (2654264967506).

27148778781601 is an frugal number, since it uses more digits than its factorization.

27148778781601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19870 (or 9935 counting only the distinct ones).

The product of its (nonzero) digits is 59006976, while the sum is 67.

The spelling of 27148778781601 in words is "twenty-seven trillion, one hundred forty-eight billion, seven hundred seventy-eight million, seven hundred eighty-one thousand, six hundred one".