449297721 has 24 divisors (see below), whose sum is σ = 672333480. Its totient is φ = 288921600.

The previous prime is 449297713. The next prime is 449297749. The reversal of 449297721 is 127792944.

It is a happy number.

449297721 is a `hidden beast` number, since 4 + 492 + 97 + 72 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 19316025 + 429981696 = 4395^2 + 20736^2 .

It is not a de Polignac number, because 449297721 - 2³ = 449297713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (449297791) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26001 + ... + 39681.

It is an arithmetic number, because the mean of its divisors is an integer number (28013895).

Almost surely, 2^449297721 is an apocalyptic number.

449297721 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

449297721 is a deficient number, since it is larger than the sum of its proper divisors (223035759).

449297721 is a wasteful number, since it uses less digits than its factorization.

449297721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13817 (or 13814 counting only the distinct ones).

The product of its digits is 254016, while the sum is 45.

The square root of 449297721 is about 21196.6440975924. The cubic root of 449297721 is about 765.9105855633.

It can be divided in two parts, 44929 and 7721, that added together give a triangular number (52650 = T₃₂₄).

The spelling of 449297721 in words is "four hundred forty-nine million, two hundred ninety-seven thousand, seven hundred twenty-one".