61587718617 has 4 divisors (see below), whose sum is σ = 82116958160. Its totient is φ = 41058479076.

The previous prime is 61587718613. The next prime is 61587718649. The reversal of 61587718617 is 71681778516.

61587718617 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 61587718617 - 2² = 61587718613 is a prime.

It is a super-3 number, since 3×61587718617³ (a number of 33 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61587718613) 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, 10264619767 + ... + 10264619772.

It is an arithmetic number, because the mean of its divisors is an integer number (20529239540).

Almost surely, 2^61587718617 is an apocalyptic number.

It is an amenable number.

61587718617 is a deficient number, since it is larger than the sum of its proper divisors (20529239543).

61587718617 is a wasteful number, since it uses less digits than its factorization.

61587718617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20529239542.

The product of its digits is 3951360, while the sum is 57.

The spelling of 61587718617 in words is "sixty-one billion, five hundred eighty-seven million, seven hundred eighteen thousand, six hundred seventeen".