1920891 has 32 divisors (see below), whose sum is σ = 3161088. Its totient is φ = 1013760.

The previous prime is 1920889. The next prime is 1920901. The reversal of 1920891 is 1980291.

It is not a de Polignac number, because 1920891 - 2¹ = 1920889 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1920811) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19755 + ... + 19851.

It is an arithmetic number, because the mean of its divisors is an integer number (98784).

2^1920891 is an apocalyptic number.

1920891 is a deficient number, since it is larger than the sum of its proper divisors (1240197).

1920891 is a wasteful number, since it uses less digits than its factorization.

1920891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171.

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 1920891 is about 1385.9621206945. The cubic root of 1920891 is about 124.3085232660.

It can be divided in two parts, 19 and 20891, that added together give a triangular number (20910 = T₂₀₄).

The spelling of 1920891 in words is "one million, nine hundred twenty thousand, eight hundred ninety-one".