816499641 has 4 divisors (see below), whose sum is σ = 1088666192. Its totient is φ = 544333092.

The previous prime is 816499631. The next prime is 816499687. The reversal of 816499641 is 146994618.

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 not a de Polignac number, because 816499641 - 2⁶ = 816499577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (816499601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136083271 + ... + 136083276.

It is an arithmetic number, because the mean of its divisors is an integer number (272166548).

Almost surely, 2^816499641 is an apocalyptic number.

It is an amenable number.

816499641 is a deficient number, since it is larger than the sum of its proper divisors (272166551).

816499641 is a wasteful number, since it uses less digits than its factorization.

816499641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272166550.

The product of its digits is 373248, while the sum is 48.

The square root of 816499641 is about 28574.4578426258. The cubic root of 816499641 is about 934.6564328187.

The spelling of 816499641 in words is "eight hundred sixteen million, four hundred ninety-nine thousand, six hundred forty-one".