1923861 has 4 divisors (see below), whose sum is σ = 2565152. Its totient is φ = 1282572.

The previous prime is 1923853. The next prime is 1923869. The reversal of 1923861 is 1683291.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1683291 = 3 ⋅561097.

It is an interprime number because it is at equal distance from previous prime (1923853) and next prime (1923869).

It is not a de Polignac number, because 1923861 - 2³ = 1923853 is a prime.

It is a super-2 number, since 2×1923861² = 7402482294642, which contains 22 as substring.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

1923861 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1923869) 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, 320641 + ... + 320646.

It is an arithmetic number, because the mean of its divisors is an integer number (641288).

2^1923861 is an apocalyptic number.

It is an amenable number.

1923861 is a deficient number, since it is larger than the sum of its proper divisors (641291).

1923861 is an equidigital number, since it uses as much as digits as its factorization.

1923861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 641290.

The product of its digits is 2592, while the sum is 30.

The square root of 1923861 is about 1387.0331647080. The cubic root of 1923861 is about 124.3725571265.

The spelling of 1923861 in words is "one million, nine hundred twenty-three thousand, eight hundred sixty-one".