81424430 has 32 divisors (see below), whose sum is σ = 151624224. Its totient is φ = 31464576.

The previous prime is 81424423. The next prime is 81424463. The reversal of 81424430 is 3442418.

It is a self number, because there is not a number n which added to its sum of digits gives 81424430.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 34364 + ... + 36656.

It is an arithmetic number, because the mean of its divisors is an integer number (4738257).

Almost surely, 2^81424430 is an apocalyptic number.

81424430 is a deficient number, since it is larger than the sum of its proper divisors (70199794).

81424430 is a wasteful number, since it uses less digits than its factorization.

81424430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2420.

The product of its (nonzero) digits is 3072, while the sum is 26.

The square root of 81424430 is about 9023.5486367615. The cubic root of 81424430 is about 433.4292759291.

Adding to 81424430 its reverse (3442418), we get a palindrome (84866848).

The spelling of 81424430 in words is "eighty-one million, four hundred twenty-four thousand, four hundred thirty".