55610507781 has 12 divisors (see below), whose sum is σ = 80746848000. Its totient is φ = 36879567720.

The previous prime is 55610507773. The next prime is 55610507801. The reversal of 55610507781 is 18770501655.

55610507781 is a `hidden beast` number, since 5 + 5 + 61 + 0 + 507 + 7 + 81 = 666.

It is not a de Polignac number, because 55610507781 - 2³ = 55610507773 is a prime.

It is a super-2 number, since 2×55610507781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55610507581) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16173531 + ... + 16176968.

It is an arithmetic number, because the mean of its divisors is an integer number (6728904000).

Almost surely, 2^55610507781 is an apocalyptic number.

It is an amenable number.

55610507781 is a deficient number, since it is larger than the sum of its proper divisors (25136340219).

55610507781 is a wasteful number, since it uses less digits than its factorization.

55610507781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32350696 (or 32350693 counting only the distinct ones).

The product of its (nonzero) digits is 294000, while the sum is 45.

It can be divided in two parts, 55610 and 507781, that added together give a triangular number (563391 = T₁₀₆₁).

The spelling of 55610507781 in words is "fifty-five billion, six hundred ten million, five hundred seven thousand, seven hundred eighty-one".