81422385 has 32 divisors (see below), whose sum is σ = 145971072. Its totient is φ = 38407680.

The previous prime is 81422339. The next prime is 81422389. The reversal of 81422385 is 58322418.

It is not a de Polignac number, because 81422385 - 2¹¹ = 81420337 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81422389) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 564 + ... + 12773.

It is an arithmetic number, because the mean of its divisors is an integer number (4561596).

Almost surely, 2^81422385 is an apocalyptic number.

It is an amenable number.

81422385 is a deficient number, since it is larger than the sum of its proper divisors (64548687).

81422385 is a wasteful number, since it uses less digits than its factorization.

81422385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13393.

The product of its digits is 15360, while the sum is 33.

The square root of 81422385 is about 9023.4353214283. The cubic root of 81422385 is about 433.4256473281.

Adding to 81422385 its sum of digits (33), we get a palindrome (81422418).

The spelling of 81422385 in words is "eighty-one million, four hundred twenty-two thousand, three hundred eighty-five".