61644169639663 has 48 divisors (see below), whose sum is σ = 70728376340160. Its totient is φ = 53385404447232.

The previous prime is 61644169639601. The next prime is 61644169639687. The reversal of 61644169639663 is 36693696144616.

It is not a de Polignac number, because 61644169639663 - 2⁴¹ = 59445146384111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61644169639592 and 61644169639601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61644169639763) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1314659523 + ... + 1314706411.

It is an arithmetic number, because the mean of its divisors is an integer number (1473507840420).

Almost surely, 2^{61644169639663} is an apocalyptic number.

61644169639663 is a deficient number, since it is larger than the sum of its proper divisors (9084206700497).

61644169639663 is a wasteful number, since it uses less digits than its factorization.

61644169639663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50608 (or 50585 counting only the distinct ones).

The product of its digits is 544195584, while the sum is 70.

The spelling of 61644169639663 in words is "sixty-one trillion, six hundred forty-four billion, one hundred sixty-nine million, six hundred thirty-nine thousand, six hundred sixty-three".