1720806122025 has 243 divisors, whose sum is σ = 3322553581893. Its totient is φ = 884044886400.

The previous prime is 1720806121981. The next prime is 1720806122039. The reversal of 1720806122025 is 5202216080271.

It is a happy number.

The square root of 1720806122025 is 1311795.

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

1720806122025 is a `hidden beast` number, since 17 + 2 + 0 + 8 + 0 + 612 + 2 + 0 + 25 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 724315038489 + 996491083536 = 851067^2 + 998244^2 .

It is a tau number, because it is divible by the number of its divisors (243).

It is not a de Polignac number, because 1720806122025 - 2⁹ = 1720806121513 is a prime.

It is a super-2 number, since 2×1720806122025² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 242 ways as a sum of consecutive naturals, for example, 21782355936 + ... + 21782356014.

Almost surely, 2^{1720806122025} is an apocalyptic number.

1720806122025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1720806122025 is the 1311795-th square number.

1720806122025 is the 655898-th centered octagonal number.

It is an amenable number.

1720806122025 is a deficient number, since it is larger than the sum of its proper divisors (1601747459868).

1720806122025 is an frugal number, since it uses more digits than its factorization.

1720806122025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274 (or 128 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

Multiplying 1720806122025 by its sum of digits (36), we get a square (61949020392900 = 7870770²).

The spelling of 1720806122025 in words is "one trillion, seven hundred twenty billion, eight hundred six million, one hundred twenty-two thousand, twenty-five".