421802813 has 4 divisors (see below), whose sum is σ = 422198460. Its totient is φ = 421407168.

The previous prime is 421802803. The next prime is 421802837. The reversal of 421802813 is 318208124.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 84235684 + 337567129 = 9178^2 + 18373^2 .

It is a cyclic number.

It is not a de Polignac number, because 421802813 - 2⁶ = 421802749 is a prime.

It is a super-2 number, since 2×421802813² = 355835226109425938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421802803) 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, 196220 + ... + 198357.

It is an arithmetic number, because the mean of its divisors is an integer number (105549615).

Almost surely, 2^421802813 is an apocalyptic number.

It is an amenable number.

421802813 is a deficient number, since it is larger than the sum of its proper divisors (395647).

421802813 is a wasteful number, since it uses less digits than its factorization.

421802813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395646.

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 421802813 is about 20537.8385668989. The cubic root of 421802813 is about 749.9572200784.

The spelling of 421802813 in words is "four hundred twenty-one million, eight hundred two thousand, eight hundred thirteen".