640516663443 has 32 divisors (see below), whose sum is σ = 890582556672. Its totient is φ = 409015152000.

The previous prime is 640516663417. The next prime is 640516663453. The reversal of 640516663443 is 344366615046.

It is a happy number.

It is not a de Polignac number, because 640516663443 - 2¹² = 640516659347 is a prime.

It is a super-2 number, since 2×640516663443² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 640516663392 and 640516663401.

It is not an unprimeable number, because it can be changed into a prime (640516663453) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35900521 + ... + 35918357.

It is an arithmetic number, because the mean of its divisors is an integer number (27830704896).

Almost surely, 2^640516663443 is an apocalyptic number.

640516663443 is a deficient number, since it is larger than the sum of its proper divisors (250065893229).

640516663443 is a wasteful number, since it uses less digits than its factorization.

640516663443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21795.

The product of its (nonzero) digits is 3732480, while the sum is 48.

The spelling of 640516663443 in words is "six hundred forty billion, five hundred sixteen million, six hundred sixty-three thousand, four hundred forty-three".