81869355 has 24 divisors (see below), whose sum is σ = 143217360. Its totient is φ = 43260480.

The previous prime is 81869341. The next prime is 81869369. The reversal of 81869355 is 55396818.

It is an interprime number because it is at equal distance from previous prime (81869341) and next prime (81869369).

It is not a de Polignac number, because 81869355 - 2⁵ = 81869323 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 81869355.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 3441 + ... + 13250.

It is an arithmetic number, because the mean of its divisors is an integer number (5967390).

Almost surely, 2^81869355 is an apocalyptic number.

81869355 is a deficient number, since it is larger than the sum of its proper divisors (61348005).

81869355 is a wasteful number, since it uses less digits than its factorization.

81869355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16811 (or 16808 counting only the distinct ones).

The product of its digits is 259200, while the sum is 45.

The square root of 81869355 is about 9048.1685992249. The cubic root of 81869355 is about 434.2173004134.

The spelling of 81869355 in words is "eighty-one million, eight hundred sixty-nine thousand, three hundred fifty-five".