640455100043 has 4 divisors (see below), whose sum is σ = 698678290968. Its totient is φ = 582231909120.

The previous prime is 640455100039. The next prime is 640455100069. The reversal of 640455100043 is 340001554046.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 640455100043 - 2² = 640455100039 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 640455099982 and 640455100009.

It is not an unprimeable number, because it can be changed into a prime (640455100003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29111595446 + ... + 29111595467.

It is an arithmetic number, because the mean of its divisors is an integer number (174669572742).

Almost surely, 2^640455100043 is an apocalyptic number.

640455100043 is a deficient number, since it is larger than the sum of its proper divisors (58223190925).

640455100043 is a wasteful number, since it uses less digits than its factorization.

640455100043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58223190924.

The product of its (nonzero) digits is 28800, while the sum is 32.

Adding to 640455100043 its reverse (340001554046), we get a palindrome (980456654089).

The spelling of 640455100043 in words is "six hundred forty billion, four hundred fifty-five million, one hundred thousand, forty-three".