645456531522 has 64 divisors (see below), whose sum is σ = 1491536332800. Its totient is φ = 184034561280.

The previous prime is 645456531521. The next prime is 645456531527. The reversal of 645456531522 is 225135654546.

It is a super-2 number, since 2×645456531522² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (645456531521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3912379 + ... + 4074017.

It is an arithmetic number, because the mean of its divisors is an integer number (23305255200).

Almost surely, 2^645456531522 is an apocalyptic number.

645456531522 is an abundant number, since it is smaller than the sum of its proper divisors (846079801278).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645456531522 is a wasteful number, since it uses less digits than its factorization.

645456531522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165231.

The product of its digits is 4320000, while the sum is 48.

The spelling of 645456531522 in words is "six hundred forty-five billion, four hundred fifty-six million, five hundred thirty-one thousand, five hundred twenty-two".