645345461 has 8 divisors (see below), whose sum is σ = 650449344. Its totient is φ = 640252800.

The previous prime is 645345451. The next prime is 645345473. The reversal of 645345461 is 164543546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645345461 - 2⁶ = 645345397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645345451) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 140741 + ... + 145253.

It is an arithmetic number, because the mean of its divisors is an integer number (81306168).

Almost surely, 2^645345461 is an apocalyptic number.

It is an amenable number.

645345461 is a deficient number, since it is larger than the sum of its proper divisors (5103883).

645345461 is a wasteful number, since it uses less digits than its factorization.

645345461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5611.

The product of its digits is 172800, while the sum is 38.

The square root of 645345461 is about 25403.6505447544. The cubic root of 645345461 is about 864.1664867821.

The spelling of 645345461 in words is "six hundred forty-five million, three hundred forty-five thousand, four hundred sixty-one".