1231780867 has 2 divisors, whose sum is σ = 1231780868. Its totient is φ = 1231780866.

The previous prime is 1231780831. The next prime is 1231780889. The reversal of 1231780867 is 7680871321.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1231780867 - 2¹⁵ = 1231748099 is a prime.

It is not a weakly prime, because it can be changed into another prime (1231780267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615890433 + 615890434.

It is an arithmetic number, because the mean of its divisors is an integer number (615890434).

Almost surely, 2^1231780867 is an apocalyptic number.

1231780867 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231780867 is an equidigital number, since it uses as much as digits as its factorization.

1231780867 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112896, while the sum is 43.

The square root of 1231780867 is about 35096.7358453746. The cubic root of 1231780867 is about 1071.9581190825.

The spelling of 1231780867 in words is "one billion, two hundred thirty-one million, seven hundred eighty thousand, eight hundred sixty-seven".