449721781 has 4 divisors (see below), whose sum is σ = 449975232. Its totient is φ = 449468332.

The previous prime is 449721751. The next prime is 449721787. The reversal of 449721781 is 187127944.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 449721781 - 2¹⁵ = 449689013 is a prime.

It is a super-2 number, since 2×449721781² = 404499360611623922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (449721787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124045 + ... + 127618.

It is an arithmetic number, because the mean of its divisors is an integer number (112493808).

Almost surely, 2^449721781 is an apocalyptic number.

It is an amenable number.

449721781 is a deficient number, since it is larger than the sum of its proper divisors (253451).

449721781 is a wasteful number, since it uses less digits than its factorization.

449721781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253450.

The product of its digits is 112896, while the sum is 43.

The square root of 449721781 is about 21206.6447369686. The cubic root of 449721781 is about 766.1514725436.

The spelling of 449721781 in words is "four hundred forty-nine million, seven hundred twenty-one thousand, seven hundred eighty-one".