61111111172 has 6 divisors (see below), whose sum is σ = 106944444558. Its totient is φ = 30555555584.

The previous prime is 61111111169. The next prime is 61111111181. The reversal of 61111111172 is 27111111116.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 53557067776 + 7554043396 = 231424^2 + 86914^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7638888893 + ... + 7638888900.

It is an arithmetic number, because the mean of its divisors is an integer number (17824074093).

Almost surely, 2^61111111172 is an apocalyptic number.

It is an amenable number.

61111111172 is a deficient number, since it is larger than the sum of its proper divisors (45833333386).

61111111172 is a wasteful number, since it uses less digits than its factorization.

61111111172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15277777797 (or 15277777795 counting only the distinct ones).

The product of its digits is 84, while the sum is 23.

Adding to 61111111172 its reverse (27111111116), we get a palindrome (88222222288).

The spelling of 61111111172 in words is "sixty-one billion, one hundred eleven million, one hundred eleven thousand, one hundred seventy-two".