79905524342121 has 75 divisors (see below), whose sum is σ = 123732843220723. Its totient is φ = 51389890201440.

The previous prime is 79905524342029. The next prime is 79905524342123. The reversal of 79905524342121 is 12124342550997.

The square root of 79905524342121 is 8938989.

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

79905524342121 is a `hidden beast` number, since 7 + 9 + 9 + 0 + 552 + 43 + 4 + 21 + 21 = 666.

It can be written as a sum of positive squares in 7 ways, for example, as 4635671669721 + 75269852672400 = 2153061^2 + 8675820^2 .

It is not a de Polignac number, because 79905524342121 - 2¹⁷ = 79905524211049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79905524342123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 74 ways as a sum of consecutive naturals, for example, 67659207151 + ... + 67659208331.

Almost surely, 2^{79905524342121} is an apocalyptic number.

79905524342121 is the 8938989-th square number.

79905524342121 is the 4469495-th centered octagonal number.

It is an amenable number.

79905524342121 is a deficient number, since it is larger than the sum of its proper divisors (43827318878602).

79905524342121 is an frugal number, since it uses more digits than its factorization.

79905524342121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2490 (or 1213 counting only the distinct ones).

The product of its (nonzero) digits is 5443200, while the sum is 54.

The spelling of 79905524342121 in words is "seventy-nine trillion, nine hundred five billion, five hundred twenty-four million, three hundred forty-two thousand, one hundred twenty-one".