15551791 has 2 divisors, whose sum is σ = 15551792. Its totient is φ = 15551790.

The previous prime is 15551779. The next prime is 15551813. The reversal of 15551791 is 19715551.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (19715551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15551791 - 2⁵ = 15551759 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15551761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7775895 + 7775896.

It is an arithmetic number, because the mean of its divisors is an integer number (7775896).

Almost surely, 2^15551791 is an apocalyptic number.

15551791 is a deficient number, since it is larger than the sum of its proper divisors (1).

15551791 is an equidigital number, since it uses as much as digits as its factorization.

15551791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7875, while the sum is 34.

The square root of 15551791 is about 3943.5759153337. The cubic root of 15551791 is about 249.6089406092.

The spelling of 15551791 in words is "fifteen million, five hundred fifty-one thousand, seven hundred ninety-one".