645415005023 has 4 divisors (see below), whose sum is σ = 645641389848. Its totient is φ = 645188620200.

The previous prime is 645415004987. The next prime is 645415005049. The reversal of 645415005023 is 320500514546.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645415005023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645415004023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113188136 + ... + 113193837.

It is an arithmetic number, because the mean of its divisors is an integer number (161410347462).

Almost surely, 2^645415005023 is an apocalyptic number.

645415005023 is a deficient number, since it is larger than the sum of its proper divisors (226384825).

645415005023 is a wasteful number, since it uses less digits than its factorization.

645415005023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226384824.

The product of its (nonzero) digits is 72000, while the sum is 35.

Adding to 645415005023 its reverse (320500514546), we get a palindrome (965915519569).

The spelling of 645415005023 in words is "six hundred forty-five billion, four hundred fifteen million, five thousand, twenty-three".