1021720677127 has 2 divisors, whose sum is σ = 1021720677128. Its totient is φ = 1021720677126.

The previous prime is 1021720677113. The next prime is 1021720677149. The reversal of 1021720677127 is 7217760271201.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1021720677127 - 2¹⁵ = 1021720644359 is a prime.

It is a super-4 number, since 4×1021720677127⁴ (a number of 49 digits) contains 4444 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021720677157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510860338563 + 510860338564.

It is an arithmetic number, because the mean of its divisors is an integer number (510860338564).

Almost surely, 2^{1021720677127} is an apocalyptic number.

1021720677127 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021720677127 is an equidigital number, since it uses as much as digits as its factorization.

1021720677127 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 115248, while the sum is 43.

The spelling of 1021720677127 in words is "one trillion, twenty-one billion, seven hundred twenty million, six hundred seventy-seven thousand, one hundred twenty-seven".