21021213413 has 4 divisors (see below), whose sum is σ = 21115479168. Its totient is φ = 20926947660.

The previous prime is 21021213391. The next prime is 21021213431. The reversal of 21021213413 is 31431212012.

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 21021213413 - 2⁶ = 21021213349 is a prime.

It is a super-2 number, since 2×21021213413² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021213013) 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, 47132543 + ... + 47132988.

It is an arithmetic number, because the mean of its divisors is an integer number (5278869792).

Almost surely, 2^21021213413 is an apocalyptic number.

It is an amenable number.

21021213413 is a deficient number, since it is larger than the sum of its proper divisors (94265755).

21021213413 is an equidigital number, since it uses as much as digits as its factorization.

21021213413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94265754.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21021213413 its reverse (31431212012), we get a palindrome (52452425425).

The spelling of 21021213413 in words is "twenty-one billion, twenty-one million, two hundred thirteen thousand, four hundred thirteen".