81215414653 has 8 divisors (see below), whose sum is σ = 81974016000. Its totient is φ = 80459660688.

The previous prime is 81215414641. The next prime is 81215414681. The reversal of 81215414653 is 35641451218.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81215414653 is a prime.

It is a super-2 number, since 2×81215414653² (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 (81215414453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 654513 + ... + 768646.

It is an arithmetic number, because the mean of its divisors is an integer number (10246752000).

Almost surely, 2^81215414653 is an apocalyptic number.

It is an amenable number.

81215414653 is a deficient number, since it is larger than the sum of its proper divisors (758601347).

81215414653 is a wasteful number, since it uses less digits than its factorization.

81215414653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1423691.

The product of its digits is 115200, while the sum is 40.

The spelling of 81215414653 in words is "eighty-one billion, two hundred fifteen million, four hundred fourteen thousand, six hundred fifty-three".