20819919523225 has 27 divisors (see below), whose sum is σ = 27425171667031. Its totient is φ = 15675882675200.

The previous prime is 20819919523213. The next prime is 20819919523229. The reversal of 20819919523225 is 52232591991802.

The square root of 20819919523225 is 4562885.

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

It can be written as a sum of positive squares in 13 ways, for example, as 9445461782409 + 11374457740816 = 3073347^2 + 3372604^2 .

It is not a de Polignac number, because 20819919523225 - 2¹⁵ = 20819919490457 is a prime.

It is a super-2 number, since 2×20819919523225² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20819919523225.

It is not an unprimeable number, because it can be changed into a prime (20819919523229) 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, 387818385 + ... + 387872065.

Almost surely, 2^{20819919523225} is an apocalyptic number.

20819919523225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20819919523225 is the 4562885-th square number.

20819919523225 is the 2281443-rd centered octagonal number.

It is an amenable number.

20819919523225 is a deficient number, since it is larger than the sum of its proper divisors (6605252143806).

20819919523225 is an frugal number, since it uses more digits than its factorization.

20819919523225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107406 (or 53703 counting only the distinct ones).

The product of its (nonzero) digits is 6998400, while the sum is 58.

The spelling of 20819919523225 in words is "twenty trillion, eight hundred nineteen billion, nine hundred nineteen million, five hundred twenty-three thousand, two hundred twenty-five".