2121253533081 has 24 divisors (see below), whose sum is σ = 3244700056104. Its totient is φ = 1330806220800.

The previous prime is 2121253533073. The next prime is 2121253533083. The reversal of 2121253533081 is 1803353521212.

2121253533081 is a `hidden beast` number, since 2 + 1 + 2 + 12 + 535 + 3 + 30 + 81 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 500215293081 + 1621038240000 = 707259^2 + 1273200^2 .

It is not a de Polignac number, because 2121253533081 - 2³ = 2121253533073 is a prime.

It is a super-2 number, since 2×2121253533081² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2121253533083) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 244381 + ... + 2074181.

It is an arithmetic number, because the mean of its divisors is an integer number (135195835671).

Almost surely, 2^{2121253533081} is an apocalyptic number.

It is an amenable number.

2121253533081 is a deficient number, since it is larger than the sum of its proper divisors (1123446523023).

2121253533081 is a wasteful number, since it uses less digits than its factorization.

2121253533081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1837401 (or 1837398 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The spelling of 2121253533081 in words is "two trillion, one hundred twenty-one billion, two hundred fifty-three million, five hundred thirty-three thousand, eighty-one".