21221000021002 has 8 divisors (see below), whose sum is σ = 31836897963396. Its totient is φ = 10608700699872.

The previous prime is 21221000020991. The next prime is 21221000021009. The reversal of 21221000021002 is 20012000012212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 14692877930641 + 6528122090361 = 3833129^2 + 2555019^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21221000021009) 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, 899640573 + ... + 899664160.

Almost surely, 2^{21221000021002} is an apocalyptic number.

21221000021002 is a deficient number, since it is larger than the sum of its proper divisors (10615897942394).

21221000021002 is a wasteful number, since it uses less digits than its factorization.

21221000021002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1799310632.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21221000021002 its reverse (20012000012212), we get a palindrome (41233000033214).

The spelling of 21221000021002 in words is "twenty-one trillion, two hundred twenty-one billion, twenty-one thousand, two".