61111721673 has 32 divisors (see below), whose sum is σ = 91606732800. Its totient is φ = 40261235328.

The previous prime is 61111721633. The next prime is 61111721681. The reversal of 61111721673 is 37612711116.

It is a happy number.

61111721673 is a `hidden beast` number, since 611 + 1 + 17 + 21 + 6 + 7 + 3 = 666.

It is not a de Polignac number, because 61111721673 - 2⁶ = 61111721609 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61111721623) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1100061 + ... + 1154277.

It is an arithmetic number, because the mean of its divisors is an integer number (2862710400).

Almost surely, 2^61111721673 is an apocalyptic number.

It is an amenable number.

61111721673 is a deficient number, since it is larger than the sum of its proper divisors (30495011127).

61111721673 is a wasteful number, since it uses less digits than its factorization.

61111721673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54718 (or 54712 counting only the distinct ones).

The product of its digits is 10584, while the sum is 36.

The spelling of 61111721673 in words is "sixty-one billion, one hundred eleven million, seven hundred twenty-one thousand, six hundred seventy-three".