20525544405 has 36 divisors (see below), whose sum is σ = 37793540772. Its totient is φ = 10303011840.

The previous prime is 20525544401. The next prime is 20525544407. The reversal of 20525544405 is 50444552502.

20525544405 is a `hidden beast` number, since 20 + 52 + 5 + 544 + 40 + 5 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 155975121 + 20369569284 = 12489^2 + 142722^2 .

It is not a de Polignac number, because 20525544405 - 2² = 20525544401 is a prime.

It is a super-3 number, since 3×20525544405³ (a number of 32 digits) contains 333 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20525544405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20525544401) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 776136 + ... + 802145.

It is an arithmetic number, because the mean of its divisors is an integer number (1049820577).

Almost surely, 2^20525544405 is an apocalyptic number.

It is an amenable number.

20525544405 is a deficient number, since it is larger than the sum of its proper divisors (17267996367).

20525544405 is a wasteful number, since it uses less digits than its factorization.

20525544405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1578326 (or 1578306 counting only the distinct ones).

The product of its (nonzero) digits is 160000, while the sum is 36.

The spelling of 20525544405 in words is "twenty billion, five hundred twenty-five million, five hundred forty-four thousand, four hundred five".