449651201981 has 2 divisors, whose sum is σ = 449651201982. Its totient is φ = 449651201980.

The previous prime is 449651201947. The next prime is 449651202029. The reversal of 449651201981 is 189102156944.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 300835795225 + 148815406756 = 548485^2 + 385766^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-449651201981 is a prime.

It is a super-2 number, since 2×449651201981² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (449651201081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 224825600990 + 224825600991.

It is an arithmetic number, because the mean of its divisors is an integer number (224825600991).

Almost surely, 2^449651201981 is an apocalyptic number.

It is an amenable number.

449651201981 is a deficient number, since it is larger than the sum of its proper divisors (1).

449651201981 is an equidigital number, since it uses as much as digits as its factorization.

449651201981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 622080, while the sum is 50.

The spelling of 449651201981 in words is "four hundred forty-nine billion, six hundred fifty-one million, two hundred one thousand, nine hundred eighty-one".