645312676 has 24 divisors (see below), whose sum is σ = 1142999480. Its totient is φ = 318753792.

The previous prime is 645312659. The next prime is 645312697. The reversal of 645312676 is 676213546.

It can be written as a sum of positive squares in 4 ways, for example, as 96628900 + 548683776 = 9830^2 + 23424^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 283270 + ... + 285538.

Almost surely, 2^645312676 is an apocalyptic number.

It is an amenable number.

645312676 is a deficient number, since it is larger than the sum of its proper divisors (497686804).

645312676 is a wasteful number, since it uses less digits than its factorization.

645312676 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3103 (or 3101 counting only the distinct ones).

The product of its digits is 181440, while the sum is 40.

The square root of 645312676 is about 25403.0052552843. The cubic root of 645312676 is about 864.1518526676.

The spelling of 645312676 in words is "six hundred forty-five million, three hundred twelve thousand, six hundred seventy-six".