81470553616 has 10 divisors (see below), whose sum is σ = 157849197662. Its totient is φ = 40735276800.

The previous prime is 81470553599. The next prime is 81470553623. The reversal of 81470553616 is 61635507418.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 68014553616 + 13456000000 = 260796^2 + 116000^2 .

It is a super-2 number, since 2×81470553616² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2545954785 + ... + 2545954816.

Almost surely, 2^81470553616 is an apocalyptic number.

It is an amenable number.

81470553616 is a deficient number, since it is larger than the sum of its proper divisors (76378644046).

81470553616 is a wasteful number, since it uses less digits than its factorization.

81470553616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5091909609 (or 5091909603 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 81470553616 in words is "eighty-one billion, four hundred seventy million, five hundred fifty-three thousand, six hundred sixteen".