640040440054 has 16 divisors (see below), whose sum is σ = 978216989760. Its totient is φ = 313968628480.

The previous prime is 640040440021. The next prime is 640040440099. The reversal of 640040440054 is 450044040046.

It is a junction number, because it is equal to n+sod(n) for n = 640040439998 and 640040440025.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2627619 + ... + 2860849.

It is an arithmetic number, because the mean of its divisors is an integer number (61138561860).

Almost surely, 2^640040440054 is an apocalyptic number.

640040440054 is a deficient number, since it is larger than the sum of its proper divisors (338176549706).

640040440054 is a wasteful number, since it uses less digits than its factorization.

640040440054 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259175.

The product of its (nonzero) digits is 30720, while the sum is 31.

The spelling of 640040440054 in words is "six hundred forty billion, forty million, four hundred forty thousand, fifty-four".