1377775921369 has 3 divisors (see below), whose sum is σ = 1377777095157. Its totient is φ = 1377774747582.

The previous prime is 1377775921339. The next prime is 1377775921381. The reversal of 1377775921369 is 9631295777731.

The square root of 1377775921369 is 1173787.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 1377775921369 - 2³⁷ = 1240336967897 is a prime.

It is a super-2 number, since 2×1377775921369² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1377775921339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 586894 + ... + 1760680.

It is an arithmetic number, because the mean of its divisors is an integer number (459259031719).

Almost surely, 2^{1377775921369} is an apocalyptic number.

1377775921369 is the 1173787-th square number.

1377775921369 is the 586894-th centered octagonal number.

It is an amenable number.

1377775921369 is a deficient number, since it is larger than the sum of its proper divisors (1173788).

1377775921369 is an frugal number, since it uses more digits than its factorization.

1377775921369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2347574 (or 1173787 counting only the distinct ones).

The product of its digits is 105019740, while the sum is 67.

The spelling of 1377775921369 in words is "one trillion, three hundred seventy-seven billion, seven hundred seventy-five million, nine hundred twenty-one thousand, three hundred sixty-nine".