2051958705221 has 4 divisors (see below), whose sum is σ = 2075014421100. Its totient is φ = 2028902989344.

The previous prime is 2051958705163. The next prime is 2051958705283. The reversal of 2051958705221 is 1225078591502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 790018768900 + 1261939936321 = 888830^2 + 1123361^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2051958705221 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 (2051958705421) 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, 11527857806 + ... + 11527857983.

It is an arithmetic number, because the mean of its divisors is an integer number (518753605275).

Almost surely, 2^{2051958705221} is an apocalyptic number.

It is an amenable number.

2051958705221 is a deficient number, since it is larger than the sum of its proper divisors (23055715879).

2051958705221 is an equidigital number, since it uses as much as digits as its factorization.

2051958705221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23055715878.

The product of its (nonzero) digits is 504000, while the sum is 47.

The spelling of 2051958705221 in words is "two trillion, fifty-one billion, nine hundred fifty-eight million, seven hundred five thousand, two hundred twenty-one".