102438421 has 2 divisors, whose sum is σ = 102438422. Its totient is φ = 102438420.

The previous prime is 102438419. The next prime is 102438439. The reversal of 102438421 is 124834201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 99500625 + 2937796 = 9975^2 + 1714^2 .

It is an emirp because it is prime and its reverse (124834201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 102438421 - 2¹ = 102438419 is a prime.

Together with 102438419, 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 (102438451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51219210 + 51219211.

It is an arithmetic number, because the mean of its divisors is an integer number (51219211).

Almost surely, 2^102438421 is an apocalyptic number.

It is an amenable number.

102438421 is a deficient number, since it is larger than the sum of its proper divisors (1).

102438421 is an equidigital number, since it uses as much as digits as its factorization.

102438421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 102438421 is about 10121.1867387179. The cubic root of 102438421 is about 467.9013431337.

The spelling of 102438421 in words is "one hundred two million, four hundred thirty-eight thousand, four hundred twenty-one".