645302621506 has 8 divisors (see below), whose sum is σ = 980206513920. Its totient is φ = 318567116868.

The previous prime is 645302621503. The next prime is 645302621521. The reversal of 645302621506 is 605126203546.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (645302621503) 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 3 ways as a sum of consecutive naturals, for example, 2042096746 + ... + 2042097061.

It is an arithmetic number, because the mean of its divisors is an integer number (122525814240).

Almost surely, 2^645302621506 is an apocalyptic number.

645302621506 is a deficient number, since it is larger than the sum of its proper divisors (334903892414).

645302621506 is a wasteful number, since it uses less digits than its factorization.

645302621506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4084193888.

The product of its (nonzero) digits is 259200, while the sum is 40.

The spelling of 645302621506 in words is "six hundred forty-five billion, three hundred two million, six hundred twenty-one thousand, five hundred six".