1231978403 has 2 divisors, whose sum is σ = 1231978404. Its totient is φ = 1231978402.

The previous prime is 1231978399. The next prime is 1231978453. The reversal of 1231978403 is 3048791321.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1231978403 - 2² = 1231978399 is a prime.

It is not a weakly prime, because it can be changed into another prime (1231978453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615989201 + 615989202.

It is an arithmetic number, because the mean of its divisors is an integer number (615989202).

Almost surely, 2^1231978403 is an apocalyptic number.

1231978403 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231978403 is an equidigital number, since it uses as much as digits as its factorization.

1231978403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 1231978403 is about 35099.5498973990. The cubic root of 1231978403 is about 1072.0154179648.

The spelling of 1231978403 in words is "one billion, two hundred thirty-one million, nine hundred seventy-eight thousand, four hundred three".