1021023 has 12 divisors (see below), whose sum is σ = 1511328. Its totient is φ = 663840.

The previous prime is 1021019. The next prime is 1021043. The reversal of 1021023 is 3201201.

It is a happy number.

It is not a de Polignac number, because 1021023 - 2² = 1021019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 1020996 and 1021014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1015 + ... + 1752.

It is an arithmetic number, because the mean of its divisors is an integer number (125944).

2^1021023 is an apocalyptic number.

1021023 is a deficient number, since it is larger than the sum of its proper divisors (490305).

1021023 is a wasteful number, since it uses less digits than its factorization.

1021023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2814 (or 2811 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 1021023 is about 1010.4568273806. The cubic root of 1021023 is about 100.6959124905.

Adding to 1021023 its reverse (3201201), we get a palindrome (4222224).

The spelling of 1021023 in words is "one million, twenty-one thousand, twenty-three".