102421 has 4 divisors (see below), whose sum is σ = 111744. Its totient is φ = 93100.

The previous prime is 102409. The next prime is 102433. The reversal of 102421 is 124201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (102409) and next prime (102433).

It is a cyclic number.

It is not a de Polignac number, because 102421 - 2⁷ = 102293 is a prime.

It is a super-2 number, since 2×102421² = 20980122482, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102398 and 102407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102451) 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, 4645 + ... + 4666.

It is an arithmetic number, because the mean of its divisors is an integer number (27936).

2¹⁰²⁴²¹ is an apocalyptic number.

102421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

102421 is a deficient number, since it is larger than the sum of its proper divisors (9323).

102421 is an equidigital number, since it uses as much as digits as its factorization.

102421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9322.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 102421 is about 320.0328108179. The cubic root of 102421 is about 46.7874817372.

Adding to 102421 its reverse (124201), we get a palindrome (226622).

The spelling of 102421 in words is "one hundred two thousand, four hundred twenty-one", and thus it is an iban number.