8427763169721 has 27 divisors (see below), whose sum is σ = 14161037831343. Its totient is φ = 4815829831680.

The previous prime is 8427763169699. The next prime is 8427763169759. The reversal of 8427763169721 is 1279613677248.

The square root of 8427763169721 is 2903061.

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

8427763169721 is a `hidden beast` number, since 8 + 427 + 76 + 31 + 6 + 97 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 603435329721 + 7824327840000 = 776811^2 + 2797200^2 .

It is not a de Polignac number, because 8427763169721 - 2²¹ = 8427761072569 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (8427763169921) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 60895161 + ... + 61033401.

Almost surely, 2^{8427763169721} is an apocalyptic number.

8427763169721 is the 2903061-st square number.

8427763169721 is the 1451531-st centered octagonal number.

It is an amenable number.

8427763169721 is a deficient number, since it is larger than the sum of its proper divisors (5733274661622).

8427763169721 is an frugal number, since it uses more digits than its factorization.

8427763169721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276502 (or 138251 counting only the distinct ones).

The product of its digits is 42674688, while the sum is 63.

The spelling of 8427763169721 in words is "eight trillion, four hundred twenty-seven billion, seven hundred sixty-three million, one hundred sixty-nine thousand, seven hundred twenty-one".