1999797 has 4 divisors (see below), whose sum is σ = 2666400. Its totient is φ = 1333196.

The previous prime is 1999771. The next prime is 1999799. The reversal of 1999797 is 7979991.

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 1999797 - 2⁶ = 1999733 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999799) 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, 333297 + ... + 333302.

It is an arithmetic number, because the mean of its divisors is an integer number (666600).

2^1999797 is an apocalyptic number.

It is an amenable number.

1999797 is a deficient number, since it is larger than the sum of its proper divisors (666603).

1999797 is an equidigital number, since it uses as much as digits as its factorization.

1999797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 666602.

The product of its digits is 321489, while the sum is 51.

The square root of 1999797 is about 1414.1417892135. The cubic root of 1999797 is about 125.9878421124.

The spelling of 1999797 in words is "one million, nine hundred ninety-nine thousand, seven hundred ninety-seven".