863221267521 has 6 divisors (see below), whose sum is σ = 1246875164210. Its totient is φ = 575480845008.

The previous prime is 863221267463. The next prime is 863221267543. The reversal of 863221267521 is 125762122368.

863221267521 is a `hidden beast` number, since 8 + 63 + 2 + 2 + 1 + 2 + 67 + 521 = 666.

It can be written as a sum of positive squares in only one way, i.e., 545920010496 + 317301257025 = 738864^2 + 563295^2 .

It is not a de Polignac number, because 863221267521 - 2⁷ = 863221267393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (863221267561) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 47956737076 + ... + 47956737093.

Almost surely, 2^863221267521 is an apocalyptic number.

It is an amenable number.

863221267521 is a deficient number, since it is larger than the sum of its proper divisors (383653896689).

863221267521 is a wasteful number, since it uses less digits than its factorization.

863221267521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95913474175 (or 95913474172 counting only the distinct ones).

The product of its digits is 483840, while the sum is 45.

Adding to 863221267521 its reverse (125762122368), we get a palindrome (988983389889).

The spelling of 863221267521 in words is "eight hundred sixty-three billion, two hundred twenty-one million, two hundred sixty-seven thousand, five hundred twenty-one".