645326361 has 12 divisors (see below), whose sum is σ = 957331492. Its totient is φ = 418589856.

The previous prime is 645326321. The next prime is 645326369. The reversal of 645326361 is 163623546.

645326361 is a `hidden beast` number, since 6 + 4 + 532 + 63 + 61 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 435974400 + 209351961 = 20880^2 + 14469^2 .

It is not a de Polignac number, because 645326361 - 2⁷ = 645326233 is a prime.

It is a super-2 number, since 2×645326361² = 832892224403004642, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (645326369) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 968626 + ... + 969291.

Almost surely, 2^645326361 is an apocalyptic number.

It is an amenable number.

645326361 is a deficient number, since it is larger than the sum of its proper divisors (312005131).

645326361 is a wasteful number, since it uses less digits than its factorization.

645326361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1937960 (or 1937957 counting only the distinct ones).

The product of its digits is 77760, while the sum is 36.

The square root of 645326361 is about 25403.2746117504. The cubic root of 645326361 is about 864.1579612488.

The spelling of 645326361 in words is "six hundred forty-five million, three hundred twenty-six thousand, three hundred sixty-one".