645689076 has 24 divisors (see below), whose sum is σ = 1508832864. Its totient is φ = 214911840.

The previous prime is 645689071. The next prime is 645689159. The reversal of 645689076 is 670986546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645689071) 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, 31195 + ... + 47586.

It is an arithmetic number, because the mean of its divisors is an integer number (62868036).

Almost surely, 2^645689076 is an apocalyptic number.

It is an amenable number.

645689076 is an abundant number, since it is smaller than the sum of its proper divisors (863143788).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645689076 is a wasteful number, since it uses less digits than its factorization.

645689076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79471 (or 79469 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 51.

The square root of 645689076 is about 25410.4127475332. The cubic root of 645689076 is about 864.3198350784.

The spelling of 645689076 in words is "six hundred forty-five million, six hundred eighty-nine thousand, seventy-six".