1921145690911 has 2 divisors, whose sum is σ = 1921145690912. Its totient is φ = 1921145690910.

The previous prime is 1921145690903. The next prime is 1921145690917. The reversal of 1921145690911 is 1190965411291.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1921145690911 - 2³ = 1921145690903 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1921145690917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 960572845455 + 960572845456.

It is an arithmetic number, because the mean of its divisors is an integer number (960572845456).

Almost surely, 2^{1921145690911} is an apocalyptic number.

1921145690911 is a deficient number, since it is larger than the sum of its proper divisors (1).

1921145690911 is an equidigital number, since it uses as much as digits as its factorization.

1921145690911 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 174960, while the sum is 49.

The spelling of 1921145690911 in words is "one trillion, nine hundred twenty-one billion, one hundred forty-five million, six hundred ninety thousand, nine hundred eleven".