1721520325825 has 12 divisors (see below), whose sum is σ = 2156692271020. Its totient is φ = 1363018152960.

The previous prime is 1721520325799. The next prime is 1721520325897. The reversal of 1721520325825 is 5285230251271.

It can be written as a sum of positive squares in 6 ways, for example, as 432316770064 + 1289203555761 = 657508^2 + 1135431^2 .

It is not a de Polignac number, because 1721520325825 - 2³⁵ = 1687160587457 is a prime.

It is a super-2 number, since 2×1721520325825² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 354950220 + ... + 354955069.

Almost surely, 2^{1721520325825} is an apocalyptic number.

It is an amenable number.

1721520325825 is a deficient number, since it is larger than the sum of its proper divisors (435171945195).

1721520325825 is an equidigital number, since it uses as much as digits as its factorization.

1721520325825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709905396 (or 709905391 counting only the distinct ones).

The product of its (nonzero) digits is 336000, while the sum is 43.

The spelling of 1721520325825 in words is "one trillion, seven hundred twenty-one billion, five hundred twenty million, three hundred twenty-five thousand, eight hundred twenty-five".