1921918 has 8 divisors (see below), whose sum is σ = 3052512. Its totient is φ = 904416.

The previous prime is 1921889. The next prime is 1921919. The reversal of 1921918 is 8191291.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1921918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921919) 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, 28230 + ... + 28297.

It is an arithmetic number, because the mean of its divisors is an integer number (381564).

2^1921918 is an apocalyptic number.

1921918 is a deficient number, since it is larger than the sum of its proper divisors (1130594).

1921918 is a wasteful number, since it uses less digits than its factorization.

1921918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56546.

The product of its digits is 1296, while the sum is 31.

The square root of 1921918 is about 1386.3325719321. The cubic root of 1921918 is about 124.3306730754.

The spelling of 1921918 in words is "one million, nine hundred twenty-one thousand, nine hundred eighteen".