19956697 has 2 divisors, whose sum is σ = 19956698. Its totient is φ = 19956696.

The previous prime is 19956679. The next prime is 19956749. The reversal of 19956697 is 79665991.

Together with previous prime (19956679) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (19956749) can be obtained adding 19956697 to its sum of digits (52).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15872256 + 4084441 = 3984^2 + 2021^2 .

It is an emirp because it is prime and its reverse (79665991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19956697 - 2⁷ = 19956569 is a prime.

It is not a weakly prime, because it can be changed into another prime (19956197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9978348 + 9978349.

It is an arithmetic number, because the mean of its divisors is an integer number (9978349).

Almost surely, 2^19956697 is an apocalyptic number.

It is an amenable number.

19956697 is a deficient number, since it is larger than the sum of its proper divisors (1).

19956697 is an equidigital number, since it uses as much as digits as its factorization.

19956697 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 918540, while the sum is 52.

The square root of 19956697 is about 4467.2919089757. The cubic root of 19956697 is about 271.2457160585.

The spelling of 19956697 in words is "nineteen million, nine hundred fifty-six thousand, six hundred ninety-seven".