21122020001 has 4 divisors (see below), whose sum is σ = 21480020400. Its totient is φ = 20764019604.

The previous prime is 21122019991. The next prime is 21122020013. The reversal of 21122020001 is 10002022112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21122020001 is a prime.

It is a super-2 number, since 2×21122020001² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21122020021) 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, 179000111 + ... + 179000228.

It is an arithmetic number, because the mean of its divisors is an integer number (5370005100).

Almost surely, 2^21122020001 is an apocalyptic number.

It is an amenable number.

21122020001 is a deficient number, since it is larger than the sum of its proper divisors (358000399).

21122020001 is an equidigital number, since it uses as much as digits as its factorization.

21122020001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358000398.

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

Adding to 21122020001 its reverse (10002022112), we get a palindrome (31124042113).

The spelling of 21122020001 in words is "twenty-one billion, one hundred twenty-two million, twenty thousand, one".