21221012013 has 8 divisors (see below), whose sum is σ = 28295565408. Its totient is φ = 14146899984.

The previous prime is 21221011961. The next prime is 21221012063. The reversal of 21221012013 is 31021012212.

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

It is not a de Polignac number, because 21221012013 - 2¹³ = 21221003821 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21221011983 and 21221012001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221012063) 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, 25870 + ... + 207632.

It is an arithmetic number, because the mean of its divisors is an integer number (3536945676).

Almost surely, 2^21221012013 is an apocalyptic number.

It is an amenable number.

21221012013 is a deficient number, since it is larger than the sum of its proper divisors (7074553395).

21221012013 is a wasteful number, since it uses less digits than its factorization.

21221012013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220683.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21221012013 its reverse (31021012212), we get a palindrome (52242024225).

The spelling of 21221012013 in words is "twenty-one billion, two hundred twenty-one million, twelve thousand, thirteen".