1377721780801 has 4 divisors (see below), whose sum is σ = 1393201800900. Its totient is φ = 1362241760704.

The previous prime is 1377721780769. The next prime is 1377721780817. The reversal of 1377721780801 is 1080871277731.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 802187131201 + 575534649600 = 895649^2 + 758640^2 .

It is a cyclic number.

It is not a de Polignac number, because 1377721780801 - 2⁵ = 1377721780769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1377721780861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7740009916 + ... + 7740010093.

It is an arithmetic number, because the mean of its divisors is an integer number (348300450225).

Almost surely, 2^{1377721780801} is an apocalyptic number.

It is an amenable number.

1377721780801 is a deficient number, since it is larger than the sum of its proper divisors (15480020099).

1377721780801 is an equidigital number, since it uses as much as digits as its factorization.

1377721780801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15480020098.

The product of its (nonzero) digits is 921984, while the sum is 52.

The spelling of 1377721780801 in words is "one trillion, three hundred seventy-seven billion, seven hundred twenty-one million, seven hundred eighty thousand, eight hundred one".