21121110001 has 8 divisors (see below), whose sum is σ = 21333996864. Its totient is φ = 20908297200.

The previous prime is 21121109923. The next prime is 21121110037. The reversal of 21121110001 is 10001112112.

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

It is a cyclic number.

It is not a de Polignac number, because 21121110001 - 2⁷ = 21121109873 is a prime.

It is a super-2 number, since 2×21121110001² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21121110001.

It is not an unprimeable number, because it can be changed into a prime (21121110041) 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, 690310 + ... + 720256.

It is an arithmetic number, because the mean of its divisors is an integer number (2666749608).

Almost surely, 2^21121110001 is an apocalyptic number.

It is an amenable number.

21121110001 is a deficient number, since it is larger than the sum of its proper divisors (212886863).

21121110001 is a wasteful number, since it uses less digits than its factorization.

21121110001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37031.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21121110001 its reverse (10001112112), we get a palindrome (31122222113).

The spelling of 21121110001 in words is "twenty-one billion, one hundred twenty-one million, one hundred ten thousand, one".