81257432653 has 8 divisors (see below), whose sum is σ = 81902304000. Its totient is φ = 80613888528.

The previous prime is 81257432647. The next prime is 81257432657. The reversal of 81257432653 is 35623475218.

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 81257432653 - 2⁵ = 81257432621 is a prime.

It is a super-2 number, since 2×81257432653² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81257432657) 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 7 ways as a sum of consecutive naturals, for example, 208693 + ... + 453946.

It is an arithmetic number, because the mean of its divisors is an integer number (10237788000).

Almost surely, 2^81257432653 is an apocalyptic number.

It is an amenable number.

81257432653 is a deficient number, since it is larger than the sum of its proper divisors (644871347).

81257432653 is a wasteful number, since it uses less digits than its factorization.

81257432653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663611.

The product of its digits is 1209600, while the sum is 46.

The spelling of 81257432653 in words is "eighty-one billion, two hundred fifty-seven million, four hundred thirty-two thousand, six hundred fifty-three".