816003440 has 40 divisors (see below), whose sum is σ = 2168239200. Its totient is φ = 279772416.

The previous prime is 816003437. The next prime is 816003449. The reversal of 816003440 is 44300618.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×816003440² = 1331723228183667200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816003449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 728015 + ... + 729134.

It is an arithmetic number, because the mean of its divisors is an integer number (54205980).

Almost surely, 2^816003440 is an apocalyptic number.

816003440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

816003440 is an abundant number, since it is smaller than the sum of its proper divisors (1352235760).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

816003440 is a wasteful number, since it uses less digits than its factorization.

816003440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1457169 (or 1457163 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 816003440 is about 28565.7739261516. The cubic root of 816003440 is about 934.4670588073.

The spelling of 816003440 in words is "eight hundred sixteen million, three thousand, four hundred forty".