640886545 has 16 divisors (see below), whose sum is σ = 831301632. Its totient is φ = 471510720.

The previous prime is 640886489. The next prime is 640886551. The reversal of 640886545 is 545688046.

It is a de Polignac number, because none of the positive numbers 2^k-640886545 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 640886495 and 640886504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 577 + ... + 35806.

It is an arithmetic number, because the mean of its divisors is an integer number (51956352).

Almost surely, 2^640886545 is an apocalyptic number.

640886545 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

640886545 is a deficient number, since it is larger than the sum of its proper divisors (190415087).

640886545 is a wasteful number, since it uses less digits than its factorization.

640886545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36672.

The product of its (nonzero) digits is 921600, while the sum is 46.

The square root of 640886545 is about 25315.7371016528. The cubic root of 640886545 is about 862.1716097734.

The spelling of 640886545 in words is "six hundred forty million, eight hundred eighty-six thousand, five hundred forty-five".