21221123001 has 32 divisors (see below), whose sum is σ = 32277813120. Its totient is φ = 12285625344.

The previous prime is 21221122987. The next prime is 21221123041. The reversal of 21221123001 is 10032112212.

It is not a de Polignac number, because 21221123001 - 2⁷ = 21221122873 is a prime.

It is a super-2 number, since 2×21221123001² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21221123041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1923166 + ... + 1934168.

It is an arithmetic number, because the mean of its divisors is an integer number (1008681660).

Almost surely, 2^21221123001 is an apocalyptic number.

It is an amenable number.

21221123001 is a deficient number, since it is larger than the sum of its proper divisors (11056690119).

21221123001 is a wasteful number, since it uses less digits than its factorization.

21221123001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13945.

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

Adding to 21221123001 its reverse (10032112212), we get a palindrome (31253235213).

The spelling of 21221123001 in words is "twenty-one billion, two hundred twenty-one million, one hundred twenty-three thousand, one".