1921965 has 16 divisors (see below), whose sum is σ = 3159168. Its totient is φ = 997056.

The previous prime is 1921937. The next prime is 1921967. The reversal of 1921965 is 5691291.

It is not a de Polignac number, because 1921965 - 2⁸ = 1921709 is a prime.

It is a super-2 number, since 2×1921965² = 7387898922450, which contains 22 as substring.

1921965 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921967) 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 15 ways as a sum of consecutive naturals, for example, 1177 + ... + 2286.

It is an arithmetic number, because the mean of its divisors is an integer number (197448).

2^1921965 is an apocalyptic number.

1921965 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1921965 is a deficient number, since it is larger than the sum of its proper divisors (1237203).

1921965 is a wasteful number, since it uses less digits than its factorization.

1921965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3508.

The product of its digits is 4860, while the sum is 33.

The square root of 1921965 is about 1386.3495230280. The cubic root of 1921965 is about 124.3316865584.

The spelling of 1921965 in words is "one million, nine hundred twenty-one thousand, nine hundred sixty-five".