645013015 has 4 divisors (see below), whose sum is σ = 774015624. Its totient is φ = 516010408.

The previous prime is 645012947. The next prime is 645013069. The reversal of 645013015 is 510310546.

645013015 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 510310546 = 2 ⋅255155273.

It is a cyclic number.

It is not a de Polignac number, because 645013015 - 2⁷ = 645012887 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64501297 + ... + 64501306.

It is an arithmetic number, because the mean of its divisors is an integer number (193503906).

Almost surely, 2^645013015 is an apocalyptic number.

645013015 is a deficient number, since it is larger than the sum of its proper divisors (129002609).

645013015 is a wasteful number, since it uses less digits than its factorization.

645013015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129002608.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 645013015 is about 25397.1064296703. The cubic root of 645013015 is about 864.0180711634.

The spelling of 645013015 in words is "six hundred forty-five million, thirteen thousand, fifteen".