81051680445 has 16 divisors (see below), whose sum is σ = 129694770432. Its totient is φ = 43223535680.

The previous prime is 81051680441. The next prime is 81051680459. The reversal of 81051680445 is 54408615018.

It is not a de Polignac number, because 81051680445 - 2² = 81051680441 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81051680397 and 81051680406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81051680441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81621 + ... + 410810.

It is an arithmetic number, because the mean of its divisors is an integer number (8105923152).

Almost surely, 2^81051680445 is an apocalyptic number.

It is an amenable number.

81051680445 is a deficient number, since it is larger than the sum of its proper divisors (48643089987).

81051680445 is a wasteful number, since it uses less digits than its factorization.

81051680445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 503412.

The product of its (nonzero) digits is 153600, while the sum is 42.

The spelling of 81051680445 in words is "eighty-one billion, fifty-one million, six hundred eighty thousand, four hundred forty-five".