1042721777791 has 2 divisors, whose sum is σ = 1042721777792. Its totient is φ = 1042721777790.

The previous prime is 1042721777743. The next prime is 1042721777837. The reversal of 1042721777791 is 1977771272401.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1042721777791 - 2¹⁹ = 1042721253503 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1042721775791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 521360888895 + 521360888896.

It is an arithmetic number, because the mean of its divisors is an integer number (521360888896).

Almost surely, 2^{1042721777791} is an apocalyptic number.

1042721777791 is a deficient number, since it is larger than the sum of its proper divisors (1).

1042721777791 is an equidigital number, since it uses as much as digits as its factorization.

1042721777791 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2420208, while the sum is 55.

The spelling of 1042721777791 in words is "one trillion, forty-two billion, seven hundred twenty-one million, seven hundred seventy-seven thousand, seven hundred ninety-one".