1204000021 has 12 divisors (see below), whose sum is σ = 1461467232. Its totient is φ = 987129528.

The previous prime is 1204000009. The next prime is 1204000033. The reversal of 1204000021 is 1200004021.

It is an interprime number because it is at equal distance from previous prime (1204000009) and next prime (1204000033).

It is not a de Polignac number, because 1204000021 - 2²¹ = 1201902869 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1203999971 and 1204000007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1204000001) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 533035 + ... + 535288.

It is an arithmetic number, because the mean of its divisors is an integer number (121788936).

Almost surely, 2^1204000021 is an apocalyptic number.

It is an amenable number.

1204000021 is a deficient number, since it is larger than the sum of its proper divisors (257467211).

1204000021 is a wasteful number, since it uses less digits than its factorization.

1204000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1068360 (or 1068353 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 1204000021 is about 34698.7034483999. The cubic root of 1204000021 is about 1063.8379976112.

Adding to 1204000021 its reverse (1200004021), we get a palindrome (2404004042).

The spelling of 1204000021 in words is "one billion, two hundred four million, twenty-one", and thus it is an aban number.