1023865891 has 2 divisors, whose sum is σ = 1023865892. Its totient is φ = 1023865890.

The previous prime is 1023865877. The next prime is 1023865951. The reversal of 1023865891 is 1985683201.

1023865891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1023865891 - 2¹¹ = 1023863843 is a prime.

It is not a weakly prime, because it can be changed into another prime (1023865841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 511932945 + 511932946.

It is an arithmetic number, because the mean of its divisors is an integer number (511932946).

Almost surely, 2^1023865891 is an apocalyptic number.

1023865891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1023865891 is an equidigital number, since it uses as much as digits as its factorization.

1023865891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 1023865891 is about 31997.9044782623. The cubic root of 1023865891 is about 1007.8928362365.

The spelling of 1023865891 in words is "one billion, twenty-three million, eight hundred sixty-five thousand, eight hundred ninety-one".