1042204021 has 2 divisors, whose sum is σ = 1042204022. Its totient is φ = 1042204020.

The previous prime is 1042204019. The next prime is 1042204061. The reversal of 1042204021 is 1204022401.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 979001521 + 63202500 = 31289^2 + 7950^2 .

It is a cyclic number.

It is not a de Polignac number, because 1042204021 - 2¹ = 1042204019 is a prime.

Together with 1042204019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1042203986 and 1042204004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1042204061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 521102010 + 521102011.

It is an arithmetic number, because the mean of its divisors is an integer number (521102011).

Almost surely, 2^1042204021 is an apocalyptic number.

It is an amenable number.

1042204021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1042204021 is an equidigital number, since it uses as much as digits as its factorization.

1042204021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 1042204021 is about 32283.1848026182. The cubic root of 1042204021 is about 1013.8746118364.

Adding to 1042204021 its reverse (1204022401), we get a palindrome (2246226422).

It can be divided in two parts, 104220 and 4021, that added together give a square (108241 = 329²).

The spelling of 1042204021 in words is "one billion, forty-two million, two hundred four thousand, twenty-one".