640654530423 has 16 divisors (see below), whose sum is σ = 891392656896. Its totient is φ = 408511679840.

The previous prime is 640654530409. The next prime is 640654530427. The reversal of 640654530423 is 324035456046.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 640654530423 - 2⁴ = 640654530407 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640654530427) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1120486 + ... + 1592732.

It is an arithmetic number, because the mean of its divisors is an integer number (55712041056).

Almost surely, 2^640654530423 is an apocalyptic number.

640654530423 is a deficient number, since it is larger than the sum of its proper divisors (250738126473).

640654530423 is a wasteful number, since it uses less digits than its factorization.

640654530423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491934.

The product of its (nonzero) digits is 1036800, while the sum is 42.

Adding to 640654530423 its reverse (324035456046), we get a palindrome (964689986469).

The spelling of 640654530423 in words is "six hundred forty billion, six hundred fifty-four million, five hundred thirty thousand, four hundred twenty-three".