640365214541 has 8 divisors (see below), whose sum is σ = 689659161240. Its totient is φ = 591076279872.

The previous prime is 640365214499. The next prime is 640365214547. The reversal of 640365214541 is 145412563046.

It can be written as a sum of positive squares in 4 ways, for example, as 1844358916 + 638520855625 = 42946^2 + 799075^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 640365214541 - 2¹⁰ = 640365213517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640365214547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 985526 + ... + 1500663.

It is an arithmetic number, because the mean of its divisors is an integer number (86207395155).

Almost surely, 2^640365214541 is an apocalyptic number.

It is an amenable number.

640365214541 is a deficient number, since it is larger than the sum of its proper divisors (49293946699).

640365214541 is a wasteful number, since it uses less digits than its factorization.

640365214541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2506015.

The product of its (nonzero) digits is 345600, while the sum is 41.

Adding to 640365214541 its reverse (145412563046), we get a palindrome (785777777587).

The spelling of 640365214541 in words is "six hundred forty billion, three hundred sixty-five million, two hundred fourteen thousand, five hundred forty-one".