111651065221 has 4 divisors (see below), whose sum is σ = 111895378732. Its totient is φ = 111406751712.

The previous prime is 111651065219. The next prime is 111651065293. The reversal of 111651065221 is 122560156111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122560156111 = 373 ⋅328579507.

It can be written as a sum of positive squares in 2 ways, for example, as 82664300196 + 28986765025 = 287514^2 + 170255^2 .

It is a cyclic number.

It is not a de Polignac number, because 111651065221 - 2¹ = 111651065219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111651065021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122156070 + ... + 122156983.

It is an arithmetic number, because the mean of its divisors is an integer number (27973844683).

Almost surely, 2^111651065221 is an apocalyptic number.

It is an amenable number.

111651065221 is a deficient number, since it is larger than the sum of its proper divisors (244313511).

111651065221 is an equidigital number, since it uses as much as digits as its factorization.

111651065221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244313510.

The product of its (nonzero) digits is 3600, while the sum is 31.

The spelling of 111651065221 in words is "one hundred eleven billion, six hundred fifty-one million, sixty-five thousand, two hundred twenty-one".