8631908636121 has 9 divisors (see below), whose sum is σ = 12468325205791. Its totient is φ = 5754599881392.

The previous prime is 8631908636101. The next prime is 8631908636149. The reversal of 8631908636121 is 1216368091368.

The square root of 8631908636121 is 2938011.

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

8631908636121 is a `hidden beast` number, since 8 + 6 + 3 + 19 + 0 + 8 + 6 + 3 + 612 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 318282147225 + 8313626488896 = 564165^2 + 2883336^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-8631908636121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8631908636101) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 8324365 + ... + 9303701.

Almost surely, 2^{8631908636121} is an apocalyptic number.

8631908636121 is the 2938011-st square number.

8631908636121 is the 1469006-th centered octagonal number.

It is an amenable number.

8631908636121 is a deficient number, since it is larger than the sum of its proper divisors (3836416569670).

8631908636121 is an frugal number, since it uses more digits than its factorization.

8631908636121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1958680 (or 979340 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 8631908636121 in words is "eight trillion, six hundred thirty-one billion, nine hundred eight million, six hundred thirty-six thousand, one hundred twenty-one".