1240991 has 2 divisors, whose sum is σ = 1240992. Its totient is φ = 1240990.

The previous prime is 1240979. The next prime is 1240999. The reversal of 1240991 is 1990421.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1240991 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1240991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1240999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620495 + 620496.

It is an arithmetic number, because the mean of its divisors is an integer number (620496).

2^1240991 is an apocalyptic number.

1240991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240991 is an equidigital number, since it uses as much as digits as its factorization.

1240991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 1240991 is about 1113.9977558326. The cubic root of 1240991 is about 107.4623195865.

The spelling of 1240991 in words is "one million, two hundred forty thousand, nine hundred ninety-one".