1373824781857 has 54 divisors (see below), whose sum is σ = 1580971321062. Its totient is φ = 1192755801600.

The previous prime is 1373824781851. The next prime is 1373824781893. The reversal of 1373824781857 is 7581874283731.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 451733196321 + 922091585536 = 672111^2 + 960256^2 .

It is not a de Polignac number, because 1373824781857 - 2⁷ = 1373824781729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1373824781851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 3936460519 + ... + 3936460867.

Almost surely, 2^{1373824781857} is an apocalyptic number.

It is an amenable number.

1373824781857 is a deficient number, since it is larger than the sum of its proper divisors (207146539205).

1373824781857 is an frugal number, since it uses more digits than its factorization.

1373824781857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879 (or 488 counting only the distinct ones).

The product of its digits is 63221760, while the sum is 64.

The spelling of 1373824781857 in words is "one trillion, three hundred seventy-three billion, eight hundred twenty-four million, seven hundred eighty-one thousand, eight hundred fifty-seven".