640502016831 has 6 divisors (see below), whose sum is σ = 925169579880. Its totient is φ = 427001344548.

The previous prime is 640502016793. The next prime is 640502016839. The reversal of 640502016831 is 138610205046.

It is a happy number.

640502016831 is a `hidden beast` number, since 64 + 0 + 502 + 0 + 1 + 68 + 31 = 666.

640502016831 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 640502016831 - 2¹³ = 640502008639 is a prime.

It is a super-2 number, since 2×640502016831² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640502016839) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35583445371 + ... + 35583445388.

It is an arithmetic number, because the mean of its divisors is an integer number (154194929980).

Almost surely, 2^640502016831 is an apocalyptic number.

640502016831 is a deficient number, since it is larger than the sum of its proper divisors (284667563049).

640502016831 is a wasteful number, since it uses less digits than its factorization.

640502016831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71166890765 (or 71166890762 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 640502016831 in words is "six hundred forty billion, five hundred two million, sixteen thousand, eight hundred thirty-one".