641660121044365 has 16 divisors (see below), whose sum is σ = 772465780090800. Its totient is φ = 511679064678912.

The previous prime is 641660121044339. The next prime is 641660121044389. The reversal of 641660121044365 is 563440121066146.

It can be written as a sum of positive squares in 8 ways, for example, as 27687991515844 + 613972129528521 = 5261938^2 + 24778461^2 .

It is a cyclic number.

It is not a de Polignac number, because 641660121044365 - 2³³ = 641651531109773 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, 86046331 + ... + 93205639.

It is an arithmetic number, because the mean of its divisors is an integer number (48279111255675).

Almost surely, 2^{641660121044365} is an apocalyptic number.

It is an amenable number.

641660121044365 is a deficient number, since it is larger than the sum of its proper divisors (130805659046435).

641660121044365 is a wasteful number, since it uses less digits than its factorization.

641660121044365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7216896.

The product of its (nonzero) digits is 2488320, while the sum is 49.

The spelling of 641660121044365 in words is "six hundred forty-one trillion, six hundred sixty billion, one hundred twenty-one million, forty-four thousand, three hundred sixty-five".