1900891 has 2 divisors, whose sum is σ = 1900892. Its totient is φ = 1900890.

The previous prime is 1900879. The next prime is 1900903. The reversal of 1900891 is 1980091.

It is a balanced prime because it is at equal distance from previous prime (1900879) and next prime (1900903).

It is a cyclic number.

It is not a de Polignac number, because 1900891 - 2⁷ = 1900763 is a prime.

It is a super-2 number, since 2×1900891² = 7226773187762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1900831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 950445 + 950446.

It is an arithmetic number, because the mean of its divisors is an integer number (950446).

2^1900891 is an apocalyptic number.

1900891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1900891 is an equidigital number, since it uses as much as digits as its factorization.

1900891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 28.

The square root of 1900891 is about 1378.7280369964. The cubic root of 1900891 is about 123.8755906223.

The spelling of 1900891 in words is "one million, nine hundred thousand, eight hundred ninety-one".