645669382 has 4 divisors (see below), whose sum is σ = 968504076. Its totient is φ = 322834690.

The previous prime is 645669371. The next prime is 645669403. The reversal of 645669382 is 283966546.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161417344 + ... + 161417347.

It is an arithmetic number, because the mean of its divisors is an integer number (242126019).

Almost surely, 2^645669382 is an apocalyptic number.

645669382 is a deficient number, since it is larger than the sum of its proper divisors (322834694).

645669382 is a wasteful number, since it uses less digits than its factorization.

645669382 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322834693.

The product of its digits is 1866240, while the sum is 49.

The square root of 645669382 is about 25410.0252262763. The cubic root of 645669382 is about 864.3110475218.

The spelling of 645669382 in words is "six hundred forty-five million, six hundred sixty-nine thousand, three hundred eighty-two".