21021210013 has 8 divisors (see below), whose sum is σ = 21327455936. Its totient is φ = 20715458400.

The previous prime is 21021209983. The next prime is 21021210029. The reversal of 21021210013 is 31001212012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21021210013 - 2⁹ = 21021209501 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21021209975 and 21021210002.

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 7 ways as a sum of consecutive naturals, for example, 37473 + ... + 208438.

It is an arithmetic number, because the mean of its divisors is an integer number (2665931992).

Almost surely, 2^21021210013 is an apocalyptic number.

It is an amenable number.

21021210013 is a deficient number, since it is larger than the sum of its proper divisors (306245923).

21021210013 is a wasteful number, since it uses less digits than its factorization.

21021210013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247155.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21021210013 its reverse (31001212012), we get a palindrome (52022422025).

The spelling of 21021210013 in words is "twenty-one billion, twenty-one million, two hundred ten thousand, thirteen".