23219999981 has 2 divisors, whose sum is σ = 23219999982. Its totient is φ = 23219999980.

The previous prime is 23219999977. The next prime is 23220000017. The reversal of 23219999981 is 18999991232.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14803588900 + 8416411081 = 121670^2 + 91741^2 .

It is a cyclic number.

It is not a de Polignac number, because 23219999981 - 2² = 23219999977 is a prime.

It is a super-2 number, since 2×23219999981² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23219999281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11609999990 + 11609999991.

It is an arithmetic number, because the mean of its divisors is an integer number (11609999991).

Almost surely, 2^23219999981 is an apocalyptic number.

It is an amenable number.

23219999981 is a deficient number, since it is larger than the sum of its proper divisors (1).

23219999981 is an equidigital number, since it uses as much as digits as its factorization.

23219999981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5668704, while the sum is 62.

The spelling of 23219999981 in words is "twenty-three billion, two hundred nineteen million, nine hundred ninety-nine thousand, nine hundred eighty-one".