1000561021 has 2 divisors, whose sum is σ = 1000561022. Its totient is φ = 1000561020.

The previous prime is 1000560983. The next prime is 1000561063. The reversal of 1000561021 is 1201650001.

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., 993195225 + 7365796 = 31515^2 + 2714^2 .

It is an emirp because it is prime and its reverse (1201650001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1000561021 - 2¹³ = 1000552829 is a prime.

It is a super-2 number, since 2×1000561021² = 2002244713489124882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1000560986 and 1000561004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1000561421) 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, 500280510 + 500280511.

It is an arithmetic number, because the mean of its divisors is an integer number (500280511).

Almost surely, 2^1000561021 is an apocalyptic number.

It is an amenable number.

1000561021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000561021 is an equidigital number, since it uses as much as digits as its factorization.

1000561021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 1000561021 is about 31631.6458787715. The cubic root of 1000561021 is about 1000.1869720393.

The spelling of 1000561021 in words is "one billion, five hundred sixty-one thousand, twenty-one".