19797287 has 4 divisors (see below), whose sum is σ = 19813080. Its totient is φ = 19781496.

The previous prime is 19797269. The next prime is 19797347. The reversal of 19797287 is 78279791.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 19797287 - 2⁶ = 19797223 is a prime.

It is a super-4 number, since 4×19797287⁴ (a number of 30 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19797187) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5837 + ... + 8582.

It is an arithmetic number, because the mean of its divisors is an integer number (4953270).

Almost surely, 2^19797287 is an apocalyptic number.

19797287 is a deficient number, since it is larger than the sum of its proper divisors (15793).

19797287 is a wasteful number, since it uses less digits than its factorization.

19797287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15792.

The product of its digits is 444528, while the sum is 50.

The square root of 19797287 is about 4449.4142311095. The cubic root of 19797287 is about 270.5215661309.

The spelling of 19797287 in words is "nineteen million, seven hundred ninety-seven thousand, two hundred eighty-seven".