81547956870 has 64 divisors (see below), whose sum is σ = 206776488960. Its totient is φ = 20525529600.

The previous prime is 81547956869. The next prime is 81547956871. The reversal of 81547956870 is 7865974518.

It is an interprime number because it is at equal distance from previous prime (81547956869) and next prime (81547956871).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81547956871) by changing a digit.

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 in 31 ways as a sum of consecutive naturals, for example, 109491 + ... + 418430.

It is an arithmetic number, because the mean of its divisors is an integer number (3230882640).

Almost surely, 2^81547956870 is an apocalyptic number.

81547956870 is an abundant number, since it is smaller than the sum of its proper divisors (125228532090).

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

81547956870 is a wasteful number, since it uses less digits than its factorization.

81547956870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528221.

The product of its (nonzero) digits is 16934400, while the sum is 60.

The spelling of 81547956870 in words is "eighty-one billion, five hundred forty-seven million, nine hundred fifty-six thousand, eight hundred seventy".