113203021 has 2 divisors, whose sum is σ = 113203022. Its totient is φ = 113203020.

The previous prime is 113203019. The next prime is 113203031. The reversal of 113203021 is 120302311.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 99800100 + 13402921 = 9990^2 + 3661^2 .

It is an emirp because it is prime and its reverse (120302311) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 113203021 - 2¹ = 113203019 is a prime.

Together with 113203019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 113202992 and 113203010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (113203031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 56601510 + 56601511.

It is an arithmetic number, because the mean of its divisors is an integer number (56601511).

Almost surely, 2^113203021 is an apocalyptic number.

It is an amenable number.

113203021 is a deficient number, since it is larger than the sum of its proper divisors (1).

113203021 is an equidigital number, since it uses as much as digits as its factorization.

113203021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 113203021 is about 10639.6908319744. The cubic root of 113203021 is about 483.7481742704.

Adding to 113203021 its reverse (120302311), we get a palindrome (233505332).

It can be divided in two parts, 11320 and 3021, that added together give a palindrome (14341).

The spelling of 113203021 in words is "one hundred thirteen million, two hundred three thousand, twenty-one".