81420498 has 32 divisors (see below), whose sum is σ = 185829120. Its totient is φ = 26406000.

The previous prime is 81420439. The next prime is 81420503. The reversal of 81420498 is 89402418.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18378 + ... + 22373.

It is an arithmetic number, because the mean of its divisors is an integer number (5807160).

Almost surely, 2^81420498 is an apocalyptic number.

81420498 is an abundant number, since it is smaller than the sum of its proper divisors (104408622).

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

81420498 is a wasteful number, since it uses less digits than its factorization.

81420498 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40799 (or 40793 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 81420498 is about 9023.3307597583. The cubic root of 81420498 is about 433.4222990249.

It can be divided in two parts, 81420 and 498, that added together give a palindrome (81918).

The spelling of 81420498 in words is "eighty-one million, four hundred twenty thousand, four hundred ninety-eight".