81368133001 has 3 divisors (see below), whose sum is σ = 81368418253. Its totient is φ = 81367847750.

The previous prime is 81368132983. The next prime is 81368133013. The reversal of 81368133001 is 10033186318.

The square root of 81368133001 is 285251.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 81368133001 - 2⁷ = 81368132873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81368133071) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 142626 + ... + 427876.

Almost surely, 2^81368133001 is an apocalyptic number.

81368133001 is the 285251-st square number.

81368133001 is the 142626-th centered octagonal number.

It is an amenable number.

81368133001 is a deficient number, since it is larger than the sum of its proper divisors (285252).

81368133001 is an frugal number, since it uses more digits than its factorization.

81368133001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570502 (or 285251 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 34.

It can be divided in two parts, 81368 and 133001, that added together give a square (214369 = 463²).

The spelling of 81368133001 in words is "eighty-one billion, three hundred sixty-eight million, one hundred thirty-three thousand, one".