61785137106851 has 4 divisors (see below), whose sum is σ = 61785162342312. Its totient is φ = 61785111871392.

The previous prime is 61785137106773. The next prime is 61785137106911. The reversal of 61785137106851 is 15860173158716.

61785137106851 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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61785137106851 is a prime.

It is a super-2 number, since 2×61785137106851² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61785137100851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8496521 + ... + 13991466.

It is an arithmetic number, because the mean of its divisors is an integer number (15446290585578).

Almost surely, 2^{61785137106851} is an apocalyptic number.

61785137106851 is a deficient number, since it is larger than the sum of its proper divisors (25235461).

61785137106851 is a wasteful number, since it uses less digits than its factorization.

61785137106851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25235460.

The product of its (nonzero) digits is 8467200, while the sum is 59.

The spelling of 61785137106851 in words is "sixty-one trillion, seven hundred eighty-five billion, one hundred thirty-seven million, one hundred six thousand, eight hundred fifty-one".