81534286653 has 32 divisors (see below), whose sum is σ = 119323373184. Its totient is φ = 49310779392.

The previous prime is 81534286633. The next prime is 81534286657. The reversal of 81534286653 is 35668243518.

81534286653 is a nontrivial binomial coefficient, being equal to C(403818, 2).

It is not a de Polignac number, because 81534286653 - 2¹³ = 81534278461 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a junction number, because it is equal to n+sod(n) for n = 81534286596 and 81534286605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81534286657) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1 + ... + 403817.

It is an arithmetic number, because the mean of its divisors is an integer number (3728855412).

Almost surely, 2^81534286653 is an apocalyptic number.

81534286653 is the 403817-th triangular number and also the 201909-th hexagonal number.

It is an amenable number.

81534286653 is a deficient number, since it is larger than the sum of its proper divisors (37789086531).

81534286653 is a wasteful number, since it uses less digits than its factorization.

81534286653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403981.

The product of its digits is 4147200, while the sum is 51.

The spelling of 81534286653 in words is "eighty-one billion, five hundred thirty-four million, two hundred eighty-six thousand, six hundred fifty-three".