645877370 has 8 divisors (see below), whose sum is σ = 1162579284. Its totient is φ = 258350944.

The previous prime is 645877327. The next prime is 645877381. The reversal of 645877370 is 73778546.

It can be written as a sum of positive squares in 2 ways, for example, as 644195161 + 1682209 = 25381^2 + 1297^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32293859 + ... + 32293878.

Almost surely, 2^645877370 is an apocalyptic number.

645877370 is a deficient number, since it is larger than the sum of its proper divisors (516701914).

645877370 is a wasteful number, since it uses less digits than its factorization.

645877370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64587744.

The product of its (nonzero) digits is 987840, while the sum is 47.

The square root of 645877370 is about 25414.1175333711. The cubic root of 645877370 is about 864.4038437382.

The spelling of 645877370 in words is "six hundred forty-five million, eight hundred seventy-seven thousand, three hundred seventy".