19861297 has 4 divisors (see below), whose sum is σ = 20502016. Its totient is φ = 19220580.

The previous prime is 19861291. The next prime is 19861333. The reversal of 19861297 is 79216891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19861297 - 2⁷ = 19861169 is a prime.

It is a super-2 number, since 2×19861297² = 788942237044418, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19861291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 320313 + ... + 320374.

It is an arithmetic number, because the mean of its divisors is an integer number (5125504).

Almost surely, 2^19861297 is an apocalyptic number.

It is an amenable number.

19861297 is a deficient number, since it is larger than the sum of its proper divisors (640719).

19861297 is an equidigital number, since it uses as much as digits as its factorization.

19861297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640718.

The product of its digits is 54432, while the sum is 43.

The square root of 19861297 is about 4456.6015078757. The cubic root of 19861297 is about 270.8128090061.

The spelling of 19861297 in words is "nineteen million, eight hundred sixty-one thousand, two hundred ninety-seven".