81358798233 has 4 divisors (see below), whose sum is σ = 108478397648. Its totient is φ = 54239198820.

The previous prime is 81358798231. The next prime is 81358798259. The reversal of 81358798233 is 33289785318.

It is a happy number.

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 not a de Polignac number, because 81358798233 - 2¹ = 81358798231 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81358798231) 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, 13559799703 + ... + 13559799708.

It is an arithmetic number, because the mean of its divisors is an integer number (27119599412).

Almost surely, 2^81358798233 is an apocalyptic number.

It is an amenable number.

81358798233 is a deficient number, since it is larger than the sum of its proper divisors (27119599415).

81358798233 is a wasteful number, since it uses less digits than its factorization.

81358798233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27119599414.

The product of its digits is 8709120, while the sum is 57.

The spelling of 81358798233 in words is "eighty-one billion, three hundred fifty-eight million, seven hundred ninety-eight thousand, two hundred thirty-three".