21202122001 has 4 divisors (see below), whose sum is σ = 21203209072. Its totient is φ = 21201034932.

The previous prime is 21202121987. The next prime is 21202122023. The reversal of 21202122001 is 10022120212.

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 not a de Polignac number, because 21202122001 - 2¹³ = 21202113809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21202122041) 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, 513735 + ... + 553468.

It is an arithmetic number, because the mean of its divisors is an integer number (5300802268).

Almost surely, 2^21202122001 is an apocalyptic number.

It is an amenable number.

21202122001 is a deficient number, since it is larger than the sum of its proper divisors (1087071).

21202122001 is a wasteful number, since it uses less digits than its factorization.

21202122001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1087070.

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

Adding to 21202122001 its reverse (10022120212), we get a palindrome (31224242213).

The spelling of 21202122001 in words is "twenty-one billion, two hundred two million, one hundred twenty-two thousand, one".