1391477392881 has 9 divisors (see below), whose sum is σ = 2009916901369. Its totient is φ = 927649236036.

The previous prime is 1391477392859. The next prime is 1391477392891. The reversal of 1391477392881 is 1882937741931.

The square root of 1391477392881 is 1179609.

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

1391477392881 is a `hidden beast` number, since 1 + 39 + 1 + 477 + 39 + 28 + 81 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 1391477392881 - 2⁹ = 1391477392369 is a prime.

It is a super-2 number, since 2×1391477392881² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1391477392891) 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 8 ways as a sum of consecutive naturals, for example, 3342226 + ... + 3735428.

Almost surely, 2^{1391477392881} is an apocalyptic number.

1391477392881 is the 1179609-th square number.

1391477392881 is the 589805-th centered octagonal number.

It is an amenable number.

1391477392881 is a deficient number, since it is larger than the sum of its proper divisors (618439508488).

1391477392881 is an frugal number, since it uses more digits than its factorization.

1391477392881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786412 (or 393206 counting only the distinct ones).

The product of its digits is 18289152, while the sum is 63.

The spelling of 1391477392881 in words is "one trillion, three hundred ninety-one billion, four hundred seventy-seven million, three hundred ninety-two thousand, eight hundred eighty-one".