20528298729 has 27 divisors (see below), whose sum is σ = 29937190647. Its totient is φ = 13555150416.

The previous prime is 20528298727. The next prime is 20528298737. The reversal of 20528298729 is 92789282502.

The square root of 20528298729 is 143277.

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

20528298729 is a `hidden beast` number, since 2 + 0 + 528 + 2 + 98 + 7 + 29 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19422603225 + 1105695504 = 139365^2 + 33252^2 .

It is not a de Polignac number, because 20528298729 - 2¹ = 20528298727 is a prime.

It is a super-2 number, since 2×20528298729² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20528298727) 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, 70062307 + ... + 70062599.

Almost surely, 2^20528298729 is an apocalyptic number.

20528298729 is the 143277-th square number.

20528298729 is the 71639-th centered octagonal number.

It is an amenable number.

20528298729 is a deficient number, since it is larger than the sum of its proper divisors (9408891918).

20528298729 is an frugal number, since it uses more digits than its factorization.

20528298729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 918 (or 459 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 20528298729 in words is "twenty billion, five hundred twenty-eight million, two hundred ninety-eight thousand, seven hundred twenty-nine".