20224521997 has 2 divisors, whose sum is σ = 20224521998. Its totient is φ = 20224521996.

The previous prime is 20224521983. The next prime is 20224522057. The reversal of 20224521997 is 79912542202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18778317156 + 1446204841 = 137034^2 + 38029^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20224521997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20224521907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10112260998 + 10112260999.

It is an arithmetic number, because the mean of its divisors is an integer number (10112260999).

Almost surely, 2^20224521997 is an apocalyptic number.

It is an amenable number.

20224521997 is a deficient number, since it is larger than the sum of its proper divisors (1).

20224521997 is an equidigital number, since it uses as much as digits as its factorization.

20224521997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 43.

The spelling of 20224521997 in words is "twenty billion, two hundred twenty-four million, five hundred twenty-one thousand, nine hundred ninety-seven".