640143256534 has 8 divisors (see below), whose sum is σ = 965190092040. Its totient is φ = 318413225856.

The previous prime is 640143256471. The next prime is 640143256573. The reversal of 640143256534 is 435652341046.

It is a happy number.

640143256534 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

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, 829200724 + ... + 829201495.

It is an arithmetic number, because the mean of its divisors is an integer number (120648761505).

Almost surely, 2^640143256534 is an apocalyptic number.

640143256534 is a deficient number, since it is larger than the sum of its proper divisors (325046835506).

640143256534 is a wasteful number, since it uses less digits than its factorization.

640143256534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1658402414.

The product of its (nonzero) digits is 1036800, while the sum is 43.

The spelling of 640143256534 in words is "six hundred forty billion, one hundred forty-three million, two hundred fifty-six thousand, five hundred thirty-four".