1928123867761 has 27 divisors (see below), whose sum is σ = 2428882768971. Its totient is φ = 1525448577744.

The previous prime is 1928123867711. The next prime is 1928123867771. The reversal of 1928123867761 is 1677683218291.

The square root of 1928123867761 is 1388569.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 285225424225 + 1642898443536 = 534065^2 + 1281756^2 .

It is not a de Polignac number, because 1928123867761 - 2¹⁵ = 1928123834993 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1928123867761.

It is not an unprimeable number, because it can be changed into a prime (1928123867711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 126352150 + ... + 126367408.

It is an arithmetic number, because the mean of its divisors is an integer number (89958621073).

Almost surely, 2^{1928123867761} is an apocalyptic number.

1928123867761 is the 1388569-th square number.

1928123867761 is the 694285-th centered octagonal number.

It is an amenable number.

1928123867761 is a deficient number, since it is larger than the sum of its proper divisors (500758901210).

1928123867761 is an frugal number, since it uses more digits than its factorization.

1928123867761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30558 (or 15279 counting only the distinct ones).

The product of its digits is 12192768, while the sum is 61.

The spelling of 1928123867761 in words is "one trillion, nine hundred twenty-eight billion, one hundred twenty-three million, eight hundred sixty-seven thousand, seven hundred sixty-one".