645715 has 16 divisors (see below), whose sum is σ = 933120. Its totient is φ = 419040.

The previous prime is 645713. The next prime is 645727. The reversal of 645715 is 517546.

It is not a de Polignac number, because 645715 - 2¹ = 645713 is a prime.

It is a super-2 number, since 2×645715² = 833895722450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 180 + ... + 1150.

It is an arithmetic number, because the mean of its divisors is an integer number (58320).

2⁶⁴⁵⁷¹⁵ is an apocalyptic number.

645715 is a deficient number, since it is larger than the sum of its proper divisors (287405).

645715 is a wasteful number, since it uses less digits than its factorization.

645715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1002.

The product of its digits is 4200, while the sum is 28.

The square root of 645715 is about 803.5639364730. The cubic root of 645715 is about 86.4331402218.

The spelling of 645715 in words is "six hundred forty-five thousand, seven hundred fifteen".