2199354991681 has 2 divisors, whose sum is σ = 2199354991682. Its totient is φ = 2199354991680.

The previous prime is 2199354991661. The next prime is 2199354991723. The reversal of 2199354991681 is 1861994539912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2196964270656 + 2390721025 = 1482216^2 + 48895^2 .

It is a cyclic number.

It is not a de Polignac number, because 2199354991681 - 2⁵ = 2199354991649 is a prime.

It is a super-2 number, since 2×2199354991681² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2199354991661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1099677495840 + 1099677495841.

It is an arithmetic number, because the mean of its divisors is an integer number (1099677495841).

Almost surely, 2^{2199354991681} is an apocalyptic number.

It is an amenable number.

2199354991681 is a deficient number, since it is larger than the sum of its proper divisors (1).

2199354991681 is an equidigital number, since it uses as much as digits as its factorization.

2199354991681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37791360, while the sum is 67.

The spelling of 2199354991681 in words is "two trillion, one hundred ninety-nine billion, three hundred fifty-four million, nine hundred ninety-one thousand, six hundred eighty-one".