81375101 has 4 divisors (see below), whose sum is σ = 82754400. Its totient is φ = 79995804.

The previous prime is 81375097. The next prime is 81375167. The reversal of 81375101 is 10157318.

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, and also an emirpimes, since its reverse is a distinct semiprime: 10157318 = 2 ⋅5078659.

It is a cyclic number.

It is not a de Polignac number, because 81375101 - 2² = 81375097 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81375181) 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, 689561 + ... + 689678.

It is an arithmetic number, because the mean of its divisors is an integer number (20688600).

Almost surely, 2^81375101 is an apocalyptic number.

It is an amenable number.

81375101 is a deficient number, since it is larger than the sum of its proper divisors (1379299).

81375101 is a wasteful number, since it uses less digits than its factorization.

81375101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1379298.

The product of its (nonzero) digits is 840, while the sum is 26.

The square root of 81375101 is about 9020.8148745000. The cubic root of 81375101 is about 433.3417307380.

The spelling of 81375101 in words is "eighty-one million, three hundred seventy-five thousand, one hundred one".