1000240991 has 2 divisors, whose sum is σ = 1000240992. Its totient is φ = 1000240990.

The previous prime is 1000240979. The next prime is 1000241027. The reversal of 1000240991 is 1990420001.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1000240991 - 2¹⁰ = 1000239967 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1000240991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1000240291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500120495 + 500120496.

It is an arithmetic number, because the mean of its divisors is an integer number (500120496).

Almost surely, 2^1000240991 is an apocalyptic number.

1000240991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000240991 is an equidigital number, since it uses as much as digits as its factorization.

1000240991 is an evil number, because the sum of its binary digits is even.

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

The square root of 1000240991 is about 31626.5867744213. The cubic root of 1000240991 is about 1000.0803238812.

Adding to 1000240991 its reverse (1990420001), we get a palindrome (2990660992).

The spelling of 1000240991 in words is "one billion, two hundred forty thousand, nine hundred ninety-one".