640528629122 has 6 divisors (see below), whose sum is σ = 960794641443. Its totient is φ = 320263748642.

The previous prime is 640528629119. The next prime is 640528629179. The reversal of 640528629122 is 221926825046.

It can be written as a sum of positive squares in only one way, i.e., 320264314561 + 320264314561 = 565919^2 + 565919^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=565919.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 848879 + ... + 1414797.

Almost surely, 2^640528629122 is an apocalyptic number.

640528629122 is a deficient number, since it is larger than the sum of its proper divisors (320266012321).

640528629122 is an frugal number, since it uses more digits than its factorization.

640528629122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1131840 (or 565921 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 47.

The spelling of 640528629122 in words is "six hundred forty billion, five hundred twenty-eight million, six hundred twenty-nine thousand, one hundred twenty-two".