640194445 has 16 divisors (see below), whose sum is σ = 841207680. Its totient is φ = 463854400.

The previous prime is 640194439. The next prime is 640194463. The reversal of 640194445 is 544491046.

It is not a de Polignac number, because 640194445 - 2³ = 640194437 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6841 + ... + 36430.

It is an arithmetic number, because the mean of its divisors is an integer number (52575480).

Almost surely, 2^640194445 is an apocalyptic number.

It is an amenable number.

640194445 is a deficient number, since it is larger than the sum of its proper divisors (201013235).

640194445 is a wasteful number, since it uses less digits than its factorization.

640194445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43556.

The product of its (nonzero) digits is 69120, while the sum is 37.

The square root of 640194445 is about 25302.0640462394. The cubic root of 640194445 is about 861.8611419784.

The spelling of 640194445 in words is "six hundred forty million, one hundred ninety-four thousand, four hundred forty-five".