1023111821 has 2 divisors, whose sum is σ = 1023111822. Its totient is φ = 1023111820.

The previous prime is 1023111811. The next prime is 1023111847. The reversal of 1023111821 is 1281113201.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 677560900 + 345550921 = 26030^2 + 18589^2 .

It is an emirp because it is prime and its reverse (1281113201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1023111821 - 2¹⁰ = 1023110797 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1023111793 and 1023111802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1023111811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 511555910 + 511555911.

It is an arithmetic number, because the mean of its divisors is an integer number (511555911).

Almost surely, 2^1023111821 is an apocalyptic number.

It is an amenable number.

1023111821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1023111821 is an equidigital number, since it uses as much as digits as its factorization.

1023111821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 20.

The square root of 1023111821 is about 31986.1191925498. The cubic root of 1023111821 is about 1007.6453401475.

The spelling of 1023111821 in words is "one billion, twenty-three million, one hundred eleven thousand, eight hundred twenty-one".