1645321215025 has 12 divisors (see below), whose sum is σ = 2063121885900. Its totient is φ = 1301467566080.

The previous prime is 1645321214987. The next prime is 1645321215049. The reversal of 1645321215025 is 5205121235461.

It can be written as a sum of positive squares in 6 ways, for example, as 55157340736 + 1590163874289 = 234856^2 + 1261017^2 .

It is not a de Polignac number, because 1645321215025 - 2¹³ = 1645321206833 is a prime.

It is a super-2 number, since 2×1645321215025² (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 11 ways as a sum of consecutive naturals, for example, 369732880 + ... + 369737329.

It is an arithmetic number, because the mean of its divisors is an integer number (171926823825).

Almost surely, 2^{1645321215025} is an apocalyptic number.

It is an amenable number.

1645321215025 is a deficient number, since it is larger than the sum of its proper divisors (417800670875).

1645321215025 is an equidigital number, since it uses as much as digits as its factorization.

1645321215025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739470308 (or 739470303 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 37.

The spelling of 1645321215025 in words is "one trillion, six hundred forty-five billion, three hundred twenty-one million, two hundred fifteen thousand, twenty-five".