81353720133470 has 16 divisors (see below), whose sum is σ = 146752974210240. Its totient is φ = 32471204060064.

The previous prime is 81353720133463. The next prime is 81353720133481. The reversal of 81353720133470 is 7433102735318.

It is a super-3 number, since 3×81353720133470³ (a number of 43 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

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, 8785494305 + ... + 8785503564.

It is an arithmetic number, because the mean of its divisors is an integer number (9172060888140).

Almost surely, 2^{81353720133470} is an apocalyptic number.

81353720133470 is a deficient number, since it is larger than the sum of its proper divisors (65399254076770).

81353720133470 is a wasteful number, since it uses less digits than its factorization.

81353720133470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17570998339.

The product of its (nonzero) digits is 1270080, while the sum is 47.

Adding to 81353720133470 its reverse (7433102735318), we get a palindrome (88786822868788).

The spelling of 81353720133470 in words is "eighty-one trillion, three hundred fifty-three billion, seven hundred twenty million, one hundred thirty-three thousand, four hundred seventy".