645863798 has 8 divisors (see below), whose sum is σ = 976191480. Its totient is φ = 320466640.

The previous prime is 645863797. The next prime is 645863809. The reversal of 645863798 is 897368546.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645863797) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1232303 + ... + 1232826.

It is an arithmetic number, because the mean of its divisors is an integer number (122023935).

Almost surely, 2^645863798 is an apocalyptic number.

645863798 is a deficient number, since it is larger than the sum of its proper divisors (330327682).

645863798 is a wasteful number, since it uses less digits than its factorization.

645863798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2465262.

The product of its digits is 8709120, while the sum is 56.

The square root of 645863798 is about 25413.8505150243. The cubic root of 645863798 is about 864.3977890433.

The spelling of 645863798 in words is "six hundred forty-five million, eight hundred sixty-three thousand, seven hundred ninety-eight".