64165620541 has 4 divisors (see below), whose sum is σ = 69998858784. Its totient is φ = 58332382300.

The previous prime is 64165620511. The next prime is 64165620577. The reversal of 64165620541 is 14502656146.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64165620541 - 2⁵ = 64165620509 is a prime.

It is a super-2 number, since 2×64165620541² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64165620494 and 64165620503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64165620511) 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, 2916619105 + ... + 2916619126.

It is an arithmetic number, because the mean of its divisors is an integer number (17499714696).

Almost surely, 2^64165620541 is an apocalyptic number.

It is an amenable number.

64165620541 is a deficient number, since it is larger than the sum of its proper divisors (5833238243).

64165620541 is a wasteful number, since it uses less digits than its factorization.

64165620541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5833238242.

The product of its (nonzero) digits is 172800, while the sum is 40.

The spelling of 64165620541 in words is "sixty-four billion, one hundred sixty-five million, six hundred twenty thousand, five hundred forty-one".