640550188738906 has 16 divisors (see below), whose sum is σ = 961772851307520. Its totient is φ = 319959368856720.

The previous prime is 640550188738891. The next prime is 640550188738921. The reversal of 640550188738906 is 609837881055046.

It is an interprime number because it is at equal distance from previous prime (640550188738891) and next prime (640550188738921).

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, 22822441 + ... + 42449548.

It is an arithmetic number, because the mean of its divisors is an integer number (60110803206720).

Almost surely, 2^{640550188738906} is an apocalyptic number.

640550188738906 is a deficient number, since it is larger than the sum of its proper divisors (321222662568614).

640550188738906 is a wasteful number, since it uses less digits than its factorization.

640550188738906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65276829.

The product of its (nonzero) digits is 348364800, while the sum is 70.

The spelling of 640550188738906 in words is "six hundred forty trillion, five hundred fifty billion, one hundred eighty-eight million, seven hundred thirty-eight thousand, nine hundred six".