81470550 has 48 divisors (see below), whose sum is σ = 230913792. Its totient is φ = 18621600.

The previous prime is 81470533. The next prime is 81470551. The reversal of 81470550 is 5507418.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81470551) 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 23 ways as a sum of consecutive naturals, for example, 37746 + ... + 39845.

It is an arithmetic number, because the mean of its divisors is an integer number (4810704).

Almost surely, 2^81470550 is an apocalyptic number.

81470550 is an abundant number, since it is smaller than the sum of its proper divisors (149443242).

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

81470550 is a wasteful number, since it uses less digits than its factorization.

81470550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77613 (or 77608 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 30.

The square root of 81470550 is about 9026.1038106151. The cubic root of 81470550 is about 433.5110940649.

Adding to 81470550 its reverse (5507418), we get a palindrome (86977968).

The spelling of 81470550 in words is "eighty-one million, four hundred seventy thousand, five hundred fifty".