102381661 has 2 divisors, whose sum is σ = 102381662. Its totient is φ = 102381660.

The previous prime is 102381659. The next prime is 102381677. The reversal of 102381661 is 166183201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 87796900 + 14584761 = 9370^2 + 3819^2 .

It is a cyclic number.

It is not a de Polignac number, because 102381661 - 2¹ = 102381659 is a prime.

Together with 102381659, 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 (102381641) 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, 51190830 + 51190831.

It is an arithmetic number, because the mean of its divisors is an integer number (51190831).

Almost surely, 2^102381661 is an apocalyptic number.

It is an amenable number.

102381661 is a deficient number, since it is larger than the sum of its proper divisors (1).

102381661 is an equidigital number, since it uses as much as digits as its factorization.

102381661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 102381661 is about 10118.3823311832. The cubic root of 102381661 is about 467.8149075084.

The spelling of 102381661 in words is "one hundred two million, three hundred eighty-one thousand, six hundred sixty-one".