1891209053 has 2 divisors, whose sum is σ = 1891209054. Its totient is φ = 1891209052.

The previous prime is 1891209031. The next prime is 1891209079. The reversal of 1891209053 is 3509021981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1270352164 + 620856889 = 35642^2 + 24917^2 .

It is a cyclic number.

It is not a de Polignac number, because 1891209053 - 2⁶ = 1891208989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1891208998 and 1891209016.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1891209253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945604526 + 945604527.

It is an arithmetic number, because the mean of its divisors is an integer number (945604527).

Almost surely, 2^1891209053 is an apocalyptic number.

It is an amenable number.

1891209053 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891209053 is an equidigital number, since it uses as much as digits as its factorization.

1891209053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 1891209053 is about 43488.0334459952. The cubic root of 1891209053 is about 1236.6491767259.

The spelling of 1891209053 in words is "one billion, eight hundred ninety-one million, two hundred nine thousand, fifty-three".