1213931 has 2 divisors, whose sum is σ = 1213932. Its totient is φ = 1213930.

The previous prime is 1213921. The next prime is 1213939. The reversal of 1213931 is 1393121.

It is a strong prime.

It is an emirp because it is prime and its reverse (1393121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1213931 - 2¹⁰ = 1212907 is a prime.

It is a super-2 number, since 2×1213931² = 2947256945522, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1213939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606965 + 606966.

It is an arithmetic number, because the mean of its divisors is an integer number (606966).

2^1213931 is an apocalyptic number.

1213931 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213931 is an equidigital number, since it uses as much as digits as its factorization.

1213931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162, while the sum is 20.

The square root of 1213931 is about 1101.7853692984. The cubic root of 1213931 is about 106.6754951460.

The spelling of 1213931 in words is "one million, two hundred thirteen thousand, nine hundred thirty-one".