102649639 has 2 divisors, whose sum is σ = 102649640. Its totient is φ = 102649638.

The previous prime is 102649637. The next prime is 102649681. The reversal of 102649639 is 936946201.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 102649639 - 2¹ = 102649637 is a prime.

Together with 102649637, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102649637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51324819 + 51324820.

It is an arithmetic number, because the mean of its divisors is an integer number (51324820).

Almost surely, 2^102649639 is an apocalyptic number.

102649639 is a deficient number, since it is larger than the sum of its proper divisors (1).

102649639 is an equidigital number, since it uses as much as digits as its factorization.

102649639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69984, while the sum is 40.

The square root of 102649639 is about 10131.6158138769. The cubic root of 102649639 is about 468.2227112860. Note that the first 3 decimals are identical.

The spelling of 102649639 in words is "one hundred two million, six hundred forty-nine thousand, six hundred thirty-nine".