102139243 has 2 divisors, whose sum is σ = 102139244. Its totient is φ = 102139242.

The previous prime is 102139237. The next prime is 102139273. The reversal of 102139243 is 342931201.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-102139243 is a prime.

It is a super-2 number, since 2×102139243² = 20864849921226098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (102139273) 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 as a sum of consecutive naturals, namely, 51069621 + 51069622.

It is an arithmetic number, because the mean of its divisors is an integer number (51069622).

Almost surely, 2^102139243 is an apocalyptic number.

102139243 is a deficient number, since it is larger than the sum of its proper divisors (1).

102139243 is an equidigital number, since it uses as much as digits as its factorization.

102139243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 102139243 is about 10106.3961430373. The cubic root of 102139243 is about 467.4453869688.

The spelling of 102139243 in words is "one hundred two million, one hundred thirty-nine thousand, two hundred forty-three".