1042120021 has 2 divisors, whose sum is σ = 1042120022. Its totient is φ = 1042120020.

The previous prime is 1042119997. The next prime is 1042120033. The reversal of 1042120021 is 1200212401.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 788991921 + 253128100 = 28089^2 + 15910^2 .

It is a cyclic number.

It is not a de Polignac number, because 1042120021 - 2¹⁵ = 1042087253 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1042119983 and 1042120010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1042120061) 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, 521060010 + 521060011.

It is an arithmetic number, because the mean of its divisors is an integer number (521060011).

Almost surely, 2^1042120021 is an apocalyptic number.

It is an amenable number.

1042120021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1042120021 is an equidigital number, since it uses as much as digits as its factorization.

1042120021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 1042120021 is about 32281.8837895189. The cubic root of 1042120021 is about 1013.8473722064.

Adding to 1042120021 its reverse (1200212401), we get a palindrome (2242332422).

The spelling of 1042120021 in words is "one billion, forty-two million, one hundred twenty thousand, twenty-one".