20278216 has 32 divisors (see below), whose sum is σ = 44858880. Its totient is φ = 8409600.

The previous prime is 20278201. The next prime is 20278253. The reversal of 20278216 is 61287202.

It is a super-2 number, since 2×20278216² = 822412088285312, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4105 + ... + 7576.

It is an arithmetic number, because the mean of its divisors is an integer number (1401840).

Almost surely, 2^20278216 is an apocalyptic number.

It is an amenable number.

20278216 is an abundant number, since it is smaller than the sum of its proper divisors (24580664).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20278216 is a wasteful number, since it uses less digits than its factorization.

20278216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11725 (or 11721 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 20278216 is about 4503.1340197689. The cubic root of 20278216 is about 272.6946273922.

The spelling of 20278216 in words is "twenty million, two hundred seventy-eight thousand, two hundred sixteen".