61549451161 has 16 divisors (see below), whose sum is σ = 67882808448. Its totient is φ = 55340467200.

The previous prime is 61549451153. The next prime is 61549451189. The reversal of 61549451161 is 16115494516.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 61549451161 - 2³ = 61549451153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61549452161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 868921 + ... + 937081.

It is an arithmetic number, because the mean of its divisors is an integer number (4242675528).

Almost surely, 2^61549451161 is an apocalyptic number.

It is an amenable number.

61549451161 is a deficient number, since it is larger than the sum of its proper divisors (6333357287).

61549451161 is a wasteful number, since it uses less digits than its factorization.

61549451161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69072.

The product of its digits is 129600, while the sum is 43.

The spelling of 61549451161 in words is "sixty-one billion, five hundred forty-nine million, four hundred fifty-one thousand, one hundred sixty-one".