420890605 has 16 divisors (see below), whose sum is σ = 510668928. Its totient is φ = 333000000.

The previous prime is 420890563. The next prime is 420890621. The reversal of 420890605 is 506098024.

420890605 = T₁₀₇ + T₁₀₈ + ... + T₁₃₆₁.

It is a happy number.

It is not a de Polignac number, because 420890605 - 2¹⁵ = 420857837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 188395 + ... + 190615.

It is an arithmetic number, because the mean of its divisors is an integer number (31916808).

Almost surely, 2^420890605 is an apocalyptic number.

It is an amenable number.

420890605 is a deficient number, since it is larger than the sum of its proper divisors (89778323).

420890605 is a wasteful number, since it uses less digits than its factorization.

420890605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2628.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 420890605 is about 20515.6185624514. The cubic root of 420890605 is about 749.4162005036.

The spelling of 420890605 in words is "four hundred twenty million, eight hundred ninety thousand, six hundred five".