1231387 has 2 divisors, whose sum is σ = 1231388. Its totient is φ = 1231386.

The previous prime is 1231381. The next prime is 1231411. The reversal of 1231387 is 7831321.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1231387 - 2³ = 1231379 is a prime.

It is not a weakly prime, because it can be changed into another prime (1231381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615693 + 615694.

It is an arithmetic number, because the mean of its divisors is an integer number (615694).

2^1231387 is an apocalyptic number.

1231387 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231387 is an equidigital number, since it uses as much as digits as its factorization.

1231387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1008, while the sum is 25.

The square root of 1231387 is about 1109.6787823510. The cubic root of 1231387 is about 107.1843852563.

The spelling of 1231387 in words is "one million, two hundred thirty-one thousand, three hundred eighty-seven".