22001115551 has 4 divisors (see below), whose sum is σ = 22053624600. Its totient is φ = 21948606504.

The previous prime is 22001115541. The next prime is 22001115559. The reversal of 22001115551 is 15551110022.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22001115551 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 (22001115559) 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, 26253896 + ... + 26254733.

It is an arithmetic number, because the mean of its divisors is an integer number (5513406150).

Almost surely, 2^22001115551 is an apocalyptic number.

22001115551 is a deficient number, since it is larger than the sum of its proper divisors (52509049).

22001115551 is an equidigital number, since it uses as much as digits as its factorization.

22001115551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52509048.

The product of its (nonzero) digits is 500, while the sum is 23.

Adding to 22001115551 its reverse (15551110022), we get a palindrome (37552225573).

The spelling of 22001115551 in words is "twenty-two billion, one million, one hundred fifteen thousand, five hundred fifty-one".