102638191 has 4 divisors (see below), whose sum is σ = 102668032. Its totient is φ = 102608352.

The previous prime is 102638183. The next prime is 102638201. The reversal of 102638191 is 191836201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 191836201 = 43 ⋅4461307.

It is a cyclic number.

It is not a de Polignac number, because 102638191 - 2³ = 102638183 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 (102633191) 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, 8970 + ... + 16903.

It is an arithmetic number, because the mean of its divisors is an integer number (25667008).

Almost surely, 2^102638191 is an apocalyptic number.

102638191 is a deficient number, since it is larger than the sum of its proper divisors (29841).

102638191 is an equidigital number, since it uses as much as digits as its factorization.

102638191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29840.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 102638191 is about 10131.0508339461. The cubic root of 102638191 is about 468.2053044611.

The spelling of 102638191 in words is "one hundred two million, six hundred thirty-eight thousand, one hundred ninety-one".