645214451015 has 4 divisors (see below), whose sum is σ = 774257341224. Its totient is φ = 516171560808.

The previous prime is 645214450999. The next prime is 645214451033. The reversal of 645214451015 is 510154412546.

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

It is a cyclic number.

It is not a de Polignac number, because 645214451015 - 2⁴ = 645214450999 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 645214451015.

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, 64521445097 + ... + 64521445106.

It is an arithmetic number, because the mean of its divisors is an integer number (193564335306).

Almost surely, 2^645214451015 is an apocalyptic number.

645214451015 is a deficient number, since it is larger than the sum of its proper divisors (129042890209).

645214451015 is a wasteful number, since it uses less digits than its factorization.

645214451015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129042890208.

The product of its (nonzero) digits is 96000, while the sum is 38.

The spelling of 645214451015 in words is "six hundred forty-five billion, two hundred fourteen million, four hundred fifty-one thousand, fifteen".