645453415625 has 12 divisors (see below), whose sum is σ = 806765137164. Its totient is φ = 516362730000.

The previous prime is 645453415573. The next prime is 645453415687. The reversal of 645453415625 is 526514354546.

It can be written as a sum of positive squares in 6 ways, for example, as 449225679049 + 196227736576 = 670243^2 + 442976^2 .

It is not a de Polignac number, because 645453415625 - 2¹⁰ = 645453414601 is a prime.

It is a super-2 number, since 2×645453415625² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

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, 103269422 + ... + 103275671.

It is an arithmetic number, because the mean of its divisors is an integer number (67230428097).

Almost surely, 2^645453415625 is an apocalyptic number.

It is an amenable number.

645453415625 is a deficient number, since it is larger than the sum of its proper divisors (161311721539).

645453415625 is an frugal number, since it uses more digits than its factorization.

645453415625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206545118 (or 206545098 counting only the distinct ones).

The product of its digits is 8640000, while the sum is 50.

The spelling of 645453415625 in words is "six hundred forty-five billion, four hundred fifty-three million, four hundred fifteen thousand, six hundred twenty-five".