1000023021 has 6 divisors (see below), whose sum is σ = 1444477710. Its totient is φ = 666682008.

The previous prime is 1000022971. The next prime is 1000023041. The reversal of 1000023021 is 1203200001.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 592386921 + 407636100 = 24339^2 + 20190^2 .

It is not a de Polignac number, because 1000023021 - 2²⁵ = 966468589 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 111113669 = 1000023021 / (1 + 0 + 0 + 0 + 0 + 2 + 3 + 0 + 2 + 1).

It is a junction number, because it is equal to n+sod(n) for n = 1000022994 and 1000023012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000023041) 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 in 5 ways as a sum of consecutive naturals, for example, 55556826 + ... + 55556843.

It is an arithmetic number, because the mean of its divisors is an integer number (240746285).

Almost surely, 2^1000023021 is an apocalyptic number.

It is an amenable number.

1000023021 is a deficient number, since it is larger than the sum of its proper divisors (444454689).

1000023021 is a wasteful number, since it uses less digits than its factorization.

1000023021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111113675 (or 111113672 counting only the distinct ones).

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

The square root of 1000023021 is about 31623.1405935590. The cubic root of 1000023021 is about 1000.0076736078.

Adding to 1000023021 its reverse (1203200001), we get a palindrome (2203223022).

The spelling of 1000023021 in words is "one billion, twenty-three thousand, twenty-one".