645344633 has 16 divisors (see below), whose sum is σ = 736827840. Its totient is φ = 561369600.

The previous prime is 645344629. The next prime is 645344653. The reversal of 645344633 is 336443546.

It is a cyclic number.

It is not a de Polignac number, because 645344633 - 2² = 645344629 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645344653) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11123 + ... + 37608.

It is an arithmetic number, because the mean of its divisors is an integer number (46051740).

Almost surely, 2^645344633 is an apocalyptic number.

It is an amenable number.

645344633 is a deficient number, since it is larger than the sum of its proper divisors (91483207).

645344633 is a wasteful number, since it uses less digits than its factorization.

645344633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48808.

The product of its digits is 311040, while the sum is 38.

The square root of 645344633 is about 25403.6342478788. The cubic root of 645344633 is about 864.1661171970.

The spelling of 645344633 in words is "six hundred forty-five million, three hundred forty-four thousand, six hundred thirty-three".