3123020021 has 16 divisors (see below), whose sum is σ = 3482403840. Its totient is φ = 2776890480.

The previous prime is 3123020009. The next prime is 3123020023. The reversal of 3123020021 is 1200203213.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 3123020021 - 2¹⁸ = 3122757877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3123019978 and 3123020005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3123020023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76190 + ... + 109776.

It is an arithmetic number, because the mean of its divisors is an integer number (217650240).

Almost surely, 2^3123020021 is an apocalyptic number.

It is an amenable number.

3123020021 is a deficient number, since it is larger than the sum of its proper divisors (359383819).

3123020021 is a wasteful number, since it uses less digits than its factorization.

3123020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33784.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 3123020021 is about 55883.9871609033. The cubic root of 3123020021 is about 1461.7000308730.

Adding to 3123020021 its reverse (1200203213), we get a palindrome (4323223234).

The spelling of 3123020021 in words is "three billion, one hundred twenty-three million, twenty thousand, twenty-one".