81420361 has 8 divisors (see below), whose sum is σ = 94047264. Its totient is φ = 69664320.

The previous prime is 81420337. The next prime is 81420379. The reversal of 81420361 is 16302418.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81420361 - 2²⁵ = 47865929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81420061) 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, 217515 + ... + 217888.

It is an arithmetic number, because the mean of its divisors is an integer number (11755908).

Almost surely, 2^81420361 is an apocalyptic number.

It is an amenable number.

81420361 is a deficient number, since it is larger than the sum of its proper divisors (12626903).

81420361 is a wasteful number, since it uses less digits than its factorization.

81420361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435431.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 81420361 is about 9023.3231683233. The cubic root of 81420361 is about 433.4220559293.

Adding to 81420361 its reverse (16302418), we get a palindrome (97722779).

The spelling of 81420361 in words is "eighty-one million, four hundred twenty thousand, three hundred sixty-one".