22001021021 has 12 divisors (see below), whose sum is σ = 25595797788. Its totient is φ = 18855974592.

The previous prime is 22001021011. The next prime is 22001021027. The reversal of 22001021021 is 12012010022.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10022812996 + 11978208025 = 100114^2 + 109445^2 .

It is not a de Polignac number, because 22001021021 - 2²² = 21996826717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22001020993 and 22001021011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22001021027) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 588335 + ... + 624611.

It is an arithmetic number, because the mean of its divisors is an integer number (2132983149).

Almost surely, 2^22001021021 is an apocalyptic number.

It is an amenable number.

22001021021 is a deficient number, since it is larger than the sum of its proper divisors (3594776767).

22001021021 is a wasteful number, since it uses less digits than its factorization.

22001021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48668 (or 48661 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 22001021021 its reverse (12012010022), we get a palindrome (34013031043).

The spelling of 22001021021 in words is "twenty-two billion, one million, twenty-one thousand, twenty-one".