1321686031 has 2 divisors, whose sum is σ = 1321686032. Its totient is φ = 1321686030.

The previous prime is 1321686017. The next prime is 1321686043. The reversal of 1321686031 is 1306861231.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321686031 is a prime.

It is a super-2 number, since 2×1321686031² = 3493707929081065922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1321685984 and 1321686002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321686001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660843015 + 660843016.

It is an arithmetic number, because the mean of its divisors is an integer number (660843016).

Almost surely, 2^1321686031 is an apocalyptic number.

1321686031 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321686031 is an equidigital number, since it uses as much as digits as its factorization.

1321686031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 1321686031 is about 36355.0000825196. Note that the first 4 decimals coincide. The cubic root of 1321686031 is about 1097.4281599501.

The spelling of 1321686031 in words is "one billion, three hundred twenty-one million, six hundred eighty-six thousand, thirty-one".