645772737 has 8 divisors (see below), whose sum is σ = 862875936. Its totient is φ = 429592352.

The previous prime is 645772669. The next prime is 645772793. The reversal of 645772737 is 737277546.

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

It is a cyclic number.

It is not a de Polignac number, because 645772737 - 2²⁸ = 377337281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645772037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 229068 + ... + 231869.

It is an arithmetic number, because the mean of its divisors is an integer number (107859492).

Almost surely, 2^645772737 is an apocalyptic number.

It is an amenable number.

645772737 is a deficient number, since it is larger than the sum of its proper divisors (217103199).

645772737 is a wasteful number, since it uses less digits than its factorization.

645772737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461407.

The product of its digits is 1728720, while the sum is 48.

The square root of 645772737 is about 25412.0588894328. The cubic root of 645772737 is about 864.3571630234.

The spelling of 645772737 in words is "six hundred forty-five million, seven hundred seventy-two thousand, seven hundred thirty-seven".