210102421 has 2 divisors, whose sum is σ = 210102422. Its totient is φ = 210102420.

The previous prime is 210102413. The next prime is 210102427. The reversal of 210102421 is 124201012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 110880900 + 99221521 = 10530^2 + 9961^2 .

It is a cyclic number.

It is not a de Polignac number, because 210102421 - 2³ = 210102413 is a prime.

It is a super-2 number, since 2×210102421² = 88286054620122482, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210102427) 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, 105051210 + 105051211.

It is an arithmetic number, because the mean of its divisors is an integer number (105051211).

Almost surely, 2^210102421 is an apocalyptic number.

It is an amenable number.

210102421 is a deficient number, since it is larger than the sum of its proper divisors (1).

210102421 is an equidigital number, since it uses as much as digits as its factorization.

210102421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 210102421 is about 14494.9101756444. The cubic root of 210102421 is about 594.4888117026.

Adding to 210102421 its reverse (124201012), we get a palindrome (334303433).

The spelling of 210102421 in words is "two hundred ten million, one hundred two thousand, four hundred twenty-one".