20278845 has 12 divisors (see below), whose sum is σ = 35150076. Its totient is φ = 10815360.

The previous prime is 20278837. The next prime is 20278879. The reversal of 20278845 is 54887202.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 15729156 + 4549689 = 3966^2 + 2133^2 .

It is not a de Polignac number, because 20278845 - 2³ = 20278837 is a prime.

It is a super-2 number, since 2×20278845² = 822463109068050, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 225276 + ... + 225365.

It is an arithmetic number, because the mean of its divisors is an integer number (2929173).

Almost surely, 2^20278845 is an apocalyptic number.

It is an amenable number.

20278845 is a deficient number, since it is larger than the sum of its proper divisors (14871231).

20278845 is a wasteful number, since it uses less digits than its factorization.

20278845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450652 (or 450649 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 36.

The square root of 20278845 is about 4503.2038594761. The cubic root of 20278845 is about 272.6974468898.

The spelling of 20278845 in words is "twenty million, two hundred seventy-eight thousand, eight hundred forty-five".