1204120021 has 8 divisors (see below), whose sum is σ = 1328373144. Its totient is φ = 1084385280.

The previous prime is 1204120019. The next prime is 1204120033. The reversal of 1204120021 is 1200214021.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 376996 + 1203743025 = 614^2 + 34695^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1204120021 - 2¹ = 1204120019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1204119983 and 1204120010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1204120051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1129036 + ... + 1130101.

It is an arithmetic number, because the mean of its divisors is an integer number (166046643).

Almost surely, 2^1204120021 is an apocalyptic number.

It is an amenable number.

1204120021 is a deficient number, since it is larger than the sum of its proper divisors (124253123).

1204120021 is a wasteful number, since it uses less digits than its factorization.

1204120021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2259191.

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

The square root of 1204120021 is about 34700.4325765544. The cubic root of 1204120021 is about 1063.8733398915.

Adding to 1204120021 its reverse (1200214021), we get a palindrome (2404334042).

The spelling of 1204120021 in words is "one billion, two hundred four million, one hundred twenty thousand, twenty-one".