440780921 has 6 divisors (see below), whose sum is σ = 512745210. Its totient is φ = 377812176.

The previous prime is 440780911. The next prime is 440780983. The reversal of 440780921 is 129087044.

It can be written as a sum of positive squares in only one way, i.e., 430770025 + 10010896 = 20755^2 + 3164^2 .

It is not a de Polignac number, because 440780921 - 2¹⁰ = 440779897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (440780911) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4497716 + ... + 4497813.

It is an arithmetic number, because the mean of its divisors is an integer number (85457535).

Almost surely, 2^440780921 is an apocalyptic number.

It is an amenable number.

440780921 is a deficient number, since it is larger than the sum of its proper divisors (71964289).

440780921 is an equidigital number, since it uses as much as digits as its factorization.

440780921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8995543 (or 8995536 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 440780921 is about 20994.7831853535. The cubic root of 440780921 is about 761.0401967298.

The spelling of 440780921 in words is "four hundred forty million, seven hundred eighty thousand, nine hundred twenty-one".