81002216533 has 4 divisors (see below), whose sum is σ = 92573961760. Its totient is φ = 69430471308.

The previous prime is 81002216531. The next prime is 81002216543. The reversal of 81002216533 is 33561220018.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81002216533 - 2¹ = 81002216531 is a prime.

It is a super-2 number, since 2×81002216533² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81002216495 and 81002216504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81002216531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5785872603 + ... + 5785872616.

It is an arithmetic number, because the mean of its divisors is an integer number (23143490440).

Almost surely, 2^81002216533 is an apocalyptic number.

It is an amenable number.

81002216533 is a deficient number, since it is larger than the sum of its proper divisors (11571745227).

81002216533 is a wasteful number, since it uses less digits than its factorization.

81002216533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11571745226.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 81002216533 in words is "eighty-one billion, two million, two hundred sixteen thousand, five hundred thirty-three".