81504851 has 16 divisors (see below), whose sum is σ = 91445760. Its totient is φ = 72190080.

The previous prime is 81504833. The next prime is 81504883. The reversal of 81504851 is 15840518.

It is a cyclic number.

It is not a de Polignac number, because 81504851 - 2²⁶ = 14395987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81504151) 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, 53186 + ... + 54696.

It is an arithmetic number, because the mean of its divisors is an integer number (5715360).

Almost surely, 2^81504851 is an apocalyptic number.

81504851 is a deficient number, since it is larger than the sum of its proper divisors (9940909).

81504851 is a wasteful number, since it uses less digits than its factorization.

81504851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1714.

The product of its (nonzero) digits is 6400, while the sum is 32.

The square root of 81504851 is about 9028.0037106771. The cubic root of 81504851 is about 433.5719249528.

The spelling of 81504851 in words is "eighty-one million, five hundred four thousand, eight hundred fifty-one".