640878876514 has 8 divisors (see below), whose sum is σ = 1017866450988. Its totient is φ = 301590059520.

The previous prime is 640878876493. The next prime is 640878876523. The reversal of 640878876514 is 415678878046.

It can be written as a sum of positive squares in 2 ways, for example, as 564278904225 + 76599972289 = 751185^2 + 276767^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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, 9424689327 + ... + 9424689394.

Almost surely, 2^640878876514 is an apocalyptic number.

640878876514 is a deficient number, since it is larger than the sum of its proper divisors (376987574474).

640878876514 is a wasteful number, since it uses less digits than its factorization.

640878876514 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18849378740.

The product of its (nonzero) digits is 72253440, while the sum is 64.

The spelling of 640878876514 in words is "six hundred forty billion, eight hundred seventy-eight million, eight hundred seventy-six thousand, five hundred fourteen".