1610111220221 has 4 divisors (see below), whose sum is σ = 1840127108832. Its totient is φ = 1380095331612.

The previous prime is 1610111220209. The next prime is 1610111220227. The reversal of 1610111220221 is 1220221110161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1610111220221 - 2¹⁸ = 1610110958077 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1610111220193 and 1610111220202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1610111220227) 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, 115007944295 + ... + 115007944308.

It is an arithmetic number, because the mean of its divisors is an integer number (460031777208).

Almost surely, 2^{1610111220221} is an apocalyptic number.

It is an amenable number.

1610111220221 is a deficient number, since it is larger than the sum of its proper divisors (230015888611).

1610111220221 is an equidigital number, since it uses as much as digits as its factorization.

1610111220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230015888610.

The product of its (nonzero) digits is 96, while the sum is 20.

Adding to 1610111220221 its reverse (1220221110161), we get a palindrome (2830332330382).

The spelling of 1610111220221 in words is "one trillion, six hundred ten billion, one hundred eleven million, two hundred twenty thousand, two hundred twenty-one".