421820687 has 2 divisors, whose sum is σ = 421820688. Its totient is φ = 421820686.

The previous prime is 421820657. The next prime is 421820701. The reversal of 421820687 is 786028124.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 421820687 - 2¹⁴ = 421804303 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 421820687.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (421820647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210910343 + 210910344.

It is an arithmetic number, because the mean of its divisors is an integer number (210910344).

Almost surely, 2^421820687 is an apocalyptic number.

421820687 is a deficient number, since it is larger than the sum of its proper divisors (1).

421820687 is an equidigital number, since it uses as much as digits as its factorization.

421820687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 421820687 is about 20538.2737103195. The cubic root of 421820687 is about 749.9678131372.

The spelling of 421820687 in words is "four hundred twenty-one million, eight hundred twenty thousand, six hundred eighty-seven".