81353420 has 24 divisors (see below), whose sum is σ = 174817104. Its totient is φ = 31784256.

The previous prime is 81353407. The next prime is 81353429. The reversal of 81353420 is 2435318.

It is a self number, because there is not a number n which added to its sum of digits gives 81353420.

It is not an unprimeable number, because it can be changed into a prime (81353429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46439 + ... + 48158.

It is an arithmetic number, because the mean of its divisors is an integer number (7284046).

Almost surely, 2^81353420 is an apocalyptic number.

It is an amenable number.

81353420 is an abundant number, since it is smaller than the sum of its proper divisors (93463684).

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

81353420 is a wasteful number, since it uses less digits than its factorization.

81353420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94649 (or 94647 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 81353420 is about 9019.6130737410. The cubic root of 81353420 is about 433.3032418289.

Adding to 81353420 its reverse (2435318), we get a palindrome (83788738).

The spelling of 81353420 in words is "eighty-one million, three hundred fifty-three thousand, four hundred twenty".