3121013021 has 4 divisors (see below), whose sum is σ = 3566872032. Its totient is φ = 2675154012.

The previous prime is 3121012987. The next prime is 3121013053. The reversal of 3121013021 is 1203101213.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1203101213 = 37 ⋅32516249.

It is a cyclic number.

It is not a de Polignac number, because 3121013021 - 2²² = 3116818717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3121012987 and 3121013005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3121013081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 222929495 + ... + 222929508.

It is an arithmetic number, because the mean of its divisors is an integer number (891718008).

Almost surely, 2^3121013021 is an apocalyptic number.

It is an amenable number.

3121013021 is a deficient number, since it is larger than the sum of its proper divisors (445859011).

3121013021 is an equidigital number, since it uses as much as digits as its factorization.

3121013021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445859010.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 3121013021 is about 55866.0274317049. The cubic root of 3121013021 is about 1461.3868446413.

Adding to 3121013021 its reverse (1203101213), we get a palindrome (4324114234).

The spelling of 3121013021 in words is "three billion, one hundred twenty-one million, thirteen thousand, twenty-one".