21221023021007 has 4 divisors (see below), whose sum is σ = 21224068962096. Its totient is φ = 21217977079920.

The previous prime is 21221023021001. The next prime is 21221023021043. The reversal of 21221023021007 is 70012032012212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21221023021007 - 2⁴² = 16822976509903 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221023021001) 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, 1522960094 + ... + 1522974027.

It is an arithmetic number, because the mean of its divisors is an integer number (5306017240524).

Almost surely, 2^{21221023021007} is an apocalyptic number.

21221023021007 is a deficient number, since it is larger than the sum of its proper divisors (3045941089).

21221023021007 is an equidigital number, since it uses as much as digits as its factorization.

21221023021007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3045941088.

The product of its (nonzero) digits is 672, while the sum is 23.

Adding to 21221023021007 its reverse (70012032012212), we get a palindrome (91233055033219).

The spelling of 21221023021007 in words is "twenty-one trillion, two hundred twenty-one billion, twenty-three million, twenty-one thousand, seven".