20247890 has 24 divisors (see below), whose sum is σ = 39468708. Its totient is φ = 7475520.

The previous prime is 20247881. The next prime is 20247893. The reversal of 20247890 is 9874202.

It can be written as a sum of positive squares in 6 ways, for example, as 6932689 + 13315201 = 2633^2 + 3649^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20247893) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 4301 + ... + 7680.

Almost surely, 2^20247890 is an apocalyptic number.

20247890 is a deficient number, since it is larger than the sum of its proper divisors (19220818).

20247890 is a wasteful number, since it uses less digits than its factorization.

20247890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12014 (or 12001 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 20247890 is about 4499.7655494481. The cubic root of 20247890 is about 272.5586216220.

The spelling of 20247890 in words is "twenty million, two hundred forty-seven thousand, eight hundred ninety".