81305179242 has 16 divisors (see below), whose sum is σ = 185840409792. Its totient is φ = 23230051200.

The previous prime is 81305179237. The next prime is 81305179283. The reversal of 81305179242 is 24297150318.

It is a super-2 number, since 2×81305179242² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42), and also a Moran number because the ratio is a prime number: 1935837601 = 81305179242 / (8 + 1 + 3 + 0 + 5 + 1 + 7 + 9 + 2 + 4 + 2).

It is a junction number, because it is equal to n+sod(n) for n = 81305179194 and 81305179203.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 967918759 + ... + 967918842.

It is an arithmetic number, because the mean of its divisors is an integer number (11615025612).

Almost surely, 2^81305179242 is an apocalyptic number.

81305179242 is an abundant number, since it is smaller than the sum of its proper divisors (104535230550).

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

81305179242 is a wasteful number, since it uses less digits than its factorization.

81305179242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1935837613.

The product of its (nonzero) digits is 120960, while the sum is 42.

The spelling of 81305179242 in words is "eighty-one billion, three hundred five million, one hundred seventy-nine thousand, two hundred forty-two".