22510551991 has 4 divisors (see below), whose sum is σ = 22524544000. Its totient is φ = 22496559984.

The previous prime is 22510551979. The next prime is 22510551997. The reversal of 22510551991 is 19915501522.

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

It is a cyclic number.

It is not a de Polignac number, because 22510551991 - 2⁷ = 22510551863 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 (22510551997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6993591 + ... + 6996808.

It is an arithmetic number, because the mean of its divisors is an integer number (5631136000).

Almost surely, 2^22510551991 is an apocalyptic number.

22510551991 is a deficient number, since it is larger than the sum of its proper divisors (13992009).

22510551991 is a wasteful number, since it uses less digits than its factorization.

22510551991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13992008.

The product of its (nonzero) digits is 40500, while the sum is 40.

The spelling of 22510551991 in words is "twenty-two billion, five hundred ten million, five hundred fifty-one thousand, nine hundred ninety-one".