51061077765 has 24 divisors (see below), whose sum is σ = 88513191000. Its totient is φ = 27230321664.

The previous prime is 51061077761. The next prime is 51061077827. The reversal of 51061077765 is 56777016015.

51061077765 is a `hidden beast` number, since 510 + 6 + 1 + 0 + 7 + 77 + 65 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 6640457121 + 44420620644 = 81489^2 + 210762^2 .

It is not a de Polignac number, because 51061077765 - 2² = 51061077761 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 51061077765.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51061077761) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 601389 + ... + 681021.

It is an arithmetic number, because the mean of its divisors is an integer number (3688049625).

Almost surely, 2^51061077765 is an apocalyptic number.

It is an amenable number.

51061077765 is a deficient number, since it is larger than the sum of its proper divisors (37452113235).

51061077765 is a wasteful number, since it uses less digits than its factorization.

51061077765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93893 (or 93890 counting only the distinct ones).

The product of its (nonzero) digits is 308700, while the sum is 45.

The spelling of 51061077765 in words is "fifty-one billion, sixty-one million, seventy-seven thousand, seven hundred sixty-five".