645920345 has 8 divisors (see below), whose sum is σ = 885833664. Its totient is φ = 442916784.

The previous prime is 645920323. The next prime is 645920347. The reversal of 645920345 is 543029546.

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 645920345 - 2⁶ = 645920281 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645920299 and 645920308.

It is not an unprimeable number, because it can be changed into a prime (645920347) 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, 9227399 + ... + 9227468.

It is an arithmetic number, because the mean of its divisors is an integer number (110729208).

Almost surely, 2^645920345 is an apocalyptic number.

It is an amenable number.

645920345 is a deficient number, since it is larger than the sum of its proper divisors (239913319).

645920345 is a wasteful number, since it uses less digits than its factorization.

645920345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18454879.

The product of its (nonzero) digits is 129600, while the sum is 38.

The square root of 645920345 is about 25414.9630139412. The cubic root of 645920345 is about 864.4230150406.

The spelling of 645920345 in words is "six hundred forty-five million, nine hundred twenty thousand, three hundred forty-five".