21121035413 has 4 divisors (see below), whose sum is σ = 21802359168. Its totient is φ = 20439711660.

The previous prime is 21121035371. The next prime is 21121035431. The reversal of 21121035413 is 31453012112.

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.

It is a cyclic number.

It is not a de Polignac number, because 21121035413 - 2¹² = 21121031317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121035473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 340661831 + ... + 340661892.

It is an arithmetic number, because the mean of its divisors is an integer number (5450589792).

Almost surely, 2^21121035413 is an apocalyptic number.

It is an amenable number.

21121035413 is a deficient number, since it is larger than the sum of its proper divisors (681323755).

21121035413 is an equidigital number, since it uses as much as digits as its factorization.

21121035413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681323754.

The product of its (nonzero) digits is 720, while the sum is 23.

Adding to 21121035413 its reverse (31453012112), we get a palindrome (52574047525).

The spelling of 21121035413 in words is "twenty-one billion, one hundred twenty-one million, thirty-five thousand, four hundred thirteen".