102691081 has 4 divisors (see below), whose sum is σ = 102712212. Its totient is φ = 102669952.

The previous prime is 102691049. The next prime is 102691091. The reversal of 102691081 is 180196201.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 180196201 = 239 ⋅753959.

It can be written as a sum of positive squares in 2 ways, for example, as 31136400 + 71554681 = 5580^2 + 8459^2 .

It is a cyclic number.

It is not a de Polignac number, because 102691081 - 2⁵ = 102691049 is a prime.

It is a super-2 number, since 2×102691081² = 21090916233897122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (102691091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 801 + ... + 14353.

It is an arithmetic number, because the mean of its divisors is an integer number (25678053).

Almost surely, 2^102691081 is an apocalyptic number.

It is an amenable number.

102691081 is a deficient number, since it is larger than the sum of its proper divisors (21131).

102691081 is an equidigital number, since it uses as much as digits as its factorization.

102691081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21130.

The product of its (nonzero) digits is 864, while the sum is 28.

The square root of 102691081 is about 10133.6607896653. The cubic root of 102691081 is about 468.2857135368.

The spelling of 102691081 in words is "one hundred two million, six hundred ninety-one thousand, eighty-one".