1389776779831 has 24 divisors (see below), whose sum is σ = 1530903628800. Its totient is φ = 1260708168720.

The previous prime is 1389776779799. The next prime is 1389776779849.

1389776779831 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1389776779831 - 2⁵ = 1389776779799 is a prime.

It is a super-2 number, since 2×1389776779831² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1389776779861) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 219100846 + ... + 219107188.

It is an arithmetic number, because the mean of its divisors is an integer number (63787651200).

Almost surely, 2^{1389776779831} is an apocalyptic number.

1389776779831 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1389776779831 is a deficient number, since it is larger than the sum of its proper divisors (141126848969).

1389776779831 is a wasteful number, since it uses less digits than its factorization.

1389776779831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9987 (or 9976 counting only the distinct ones).

The product of its digits is 672126336, while the sum is 76.

The spelling of 1389776779831 in words is "one trillion, three hundred eighty-nine billion, seven hundred seventy-six million, seven hundred seventy-nine thousand, eight hundred thirty-one".