20729557949225 has 12 divisors (see below), whose sum is σ = 25736425246620. Its totient is φ = 16563147398400.

The previous prime is 20729557949183. The next prime is 20729557949263. The reversal of 20729557949225 is 52294975592702.

It can be written as a sum of positive squares in 6 ways, for example, as 3916441 + 20729554032784 = 1979^2 + 4552972^2 .

It is not a de Polignac number, because 20729557949225 - 2⁸ = 20729557948969 is a prime.

It is a Curzon number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 512453396 + ... + 512493845.

It is an arithmetic number, because the mean of its divisors is an integer number (2144702103885).

Almost surely, 2^{20729557949225} is an apocalyptic number.

20729557949225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20729557949225 is a deficient number, since it is larger than the sum of its proper divisors (5006867297395).

20729557949225 is a wasteful number, since it uses less digits than its factorization.

20729557949225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1024948060 (or 1024948055 counting only the distinct ones).

The product of its (nonzero) digits is 285768000, while the sum is 68.

The spelling of 20729557949225 in words is "twenty trillion, seven hundred twenty-nine billion, five hundred fifty-seven million, nine hundred forty-nine thousand, two hundred twenty-five".