421286581 has 2 divisors, whose sum is σ = 421286582. Its totient is φ = 421286580.

The previous prime is 421286543. The next prime is 421286587. The reversal of 421286581 is 185682124.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 280864081 + 140422500 = 16759^2 + 11850^2 .

It is a cyclic number.

It is not a de Polignac number, because 421286581 - 2¹⁵ = 421253813 is a prime.

It is a super-2 number, since 2×421286581² = 354964766661339122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 421286581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (421286587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210643290 + 210643291.

It is an arithmetic number, because the mean of its divisors is an integer number (210643291).

Almost surely, 2^421286581 is an apocalyptic number.

It is an amenable number.

421286581 is a deficient number, since it is larger than the sum of its proper divisors (1).

421286581 is an equidigital number, since it uses as much as digits as its factorization.

421286581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30720, while the sum is 37.

The square root of 421286581 is about 20525.2668922964. The cubic root of 421286581 is about 749.6511450180.

The spelling of 421286581 in words is "four hundred twenty-one million, two hundred eighty-six thousand, five hundred eighty-one".