81326311545 has 8 divisors (see below), whose sum is σ = 130122098496. Its totient is φ = 43374032816.

The previous prime is 81326311541. The next prime is 81326311579. The reversal of 81326311545 is 54511362318.

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

It is a cyclic number.

It is not a de Polignac number, because 81326311545 - 2² = 81326311541 is a prime.

It is a super-2 number, since 2×81326311545² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81326311541) 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, 2710877037 + ... + 2710877066.

It is an arithmetic number, because the mean of its divisors is an integer number (16265262312).

Almost surely, 2^81326311545 is an apocalyptic number.

It is an amenable number.

81326311545 is a deficient number, since it is larger than the sum of its proper divisors (48795786951).

81326311545 is a wasteful number, since it uses less digits than its factorization.

81326311545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5421754111.

The product of its digits is 86400, while the sum is 39.

The spelling of 81326311545 in words is "eighty-one billion, three hundred twenty-six million, three hundred eleven thousand, five hundred forty-five".