81264890 has 16 divisors (see below), whose sum is σ = 167173632. Its totient is φ = 27862224.

The previous prime is 81264877. The next prime is 81264893. The reversal of 81264890 is 9846218.

It is not an unprimeable number, because it can be changed into a prime (81264893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 580394 + ... + 580533.

It is an arithmetic number, because the mean of its divisors is an integer number (10448352).

Almost surely, 2^81264890 is an apocalyptic number.

81264890 is an abundant number, since it is smaller than the sum of its proper divisors (85908742).

81264890 is a wasteful number, since it uses less digits than its factorization.

81264890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1160941.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 81264890 is about 9014.7040994145. The cubic root of 81264890 is about 433.1460091062.

The spelling of 81264890 in words is "eighty-one million, two hundred sixty-four thousand, eight hundred ninety".