1510991 has 2 divisors, whose sum is σ = 1510992. Its totient is φ = 1510990.

The previous prime is 1510967. The next prime is 1511017. The reversal of 1510991 is 1990151.

It is a happy number.

It is an a-pointer prime, because the next prime (1511017) can be obtained adding 1510991 to its sum of digits (26).

It is a weak prime.

It is an emirp because it is prime and its reverse (1990151) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1510991 - 2¹⁰ = 1509967 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is equal to p₁₁₄₉₆₅ and since 1510991 and 114965 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1510991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1510921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 755495 + 755496.

It is an arithmetic number, because the mean of its divisors is an integer number (755496).

2^1510991 is an apocalyptic number.

1510991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1510991 is an equidigital number, since it uses as much as digits as its factorization.

1510991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 405, while the sum is 26.

The square root of 1510991 is about 1229.2237387880. The cubic root of 1510991 is about 114.7503342326.

The spelling of 1510991 in words is "one million, five hundred ten thousand, nine hundred ninety-one".