816261987 has 16 divisors (see below), whose sum is σ = 1165324320. Its totient is φ = 506406912.

The previous prime is 816261967. The next prime is 816262033. The reversal of 816261987 is 789162618.

816261987 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 816261987 - 2¹² = 816257891 is a prime.

It is not an unprimeable number, because it can be changed into a prime (816261947) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85378 + ... + 94455.

It is an arithmetic number, because the mean of its divisors is an integer number (72832770).

Almost surely, 2^816261987 is an apocalyptic number.

816261987 is a deficient number, since it is larger than the sum of its proper divisors (349062333).

816261987 is a wasteful number, since it uses less digits than its factorization.

816261987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179942.

The product of its digits is 290304, while the sum is 48.

The square root of 816261987 is about 28570.2990358869. The cubic root of 816261987 is about 934.5657422729.

The spelling of 816261987 in words is "eight hundred sixteen million, two hundred sixty-one thousand, nine hundred eighty-seven".