61753077781 has 4 divisors (see below), whose sum is σ = 61856172000. Its totient is φ = 61649983564.

The previous prime is 61753077773. The next prime is 61753077809. The reversal of 61753077781 is 18777035716.

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 61753077781 - 2³ = 61753077773 is a prime.

It is a super-2 number, since 2×61753077781² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61753077731) 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, 51546211 + ... + 51547408.

It is an arithmetic number, because the mean of its divisors is an integer number (15464043000).

Almost surely, 2^61753077781 is an apocalyptic number.

It is an amenable number.

61753077781 is a deficient number, since it is larger than the sum of its proper divisors (103094219).

61753077781 is a wasteful number, since it uses less digits than its factorization.

61753077781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103094218.

The product of its (nonzero) digits is 1728720, while the sum is 52.

The spelling of 61753077781 in words is "sixty-one billion, seven hundred fifty-three million, seventy-seven thousand, seven hundred eighty-one".