2051221567121 has 16 divisors (see below), whose sum is σ = 2138610764928. Its totient is φ = 1965593174400.

The previous prime is 2051221567091. The next prime is 2051221567147. The reversal of 2051221567121 is 1217651221502.

It is a cyclic number.

It is not a de Polignac number, because 2051221567121 - 2¹⁴ = 2051221550737 is a prime.

It is a super-2 number, since 2×2051221567121² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2051221567721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1316876 + ... + 2415906.

It is an arithmetic number, because the mean of its divisors is an integer number (133663172808).

Almost surely, 2^{2051221567121} is an apocalyptic number.

It is an amenable number.

2051221567121 is a deficient number, since it is larger than the sum of its proper divisors (87389197807).

2051221567121 is a wasteful number, since it uses less digits than its factorization.

2051221567121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1099832.

The product of its (nonzero) digits is 16800, while the sum is 35.

Adding to 2051221567121 its reverse (1217651221502), we get a palindrome (3268872788623).

The spelling of 2051221567121 in words is "two trillion, fifty-one billion, two hundred twenty-one million, five hundred sixty-seven thousand, one hundred twenty-one".