13720028 has 12 divisors (see below), whose sum is σ = 27440112. Its totient is φ = 5880000.

The previous prime is 13720001. The next prime is 13720039. The reversal of 13720028 is 82002731.

13720028 = 1397² + 1398² + ... + 1403².

13720028 is an admirable number.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 13719985 and 13720012.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 244973 + ... + 245028.

It is an arithmetic number, because the mean of its divisors is an integer number (2286676).

Almost surely, 2^13720028 is an apocalyptic number.

It is an amenable number.

13720028 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

13720028 is a wasteful number, since it uses less digits than its factorization.

13720028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490012 (or 490010 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 13720028 is about 3704.0556151332. The cubic root of 13720028 is about 239.3967953895.

Adding to 13720028 its reverse (82002731), we get a palindrome (95722759).

It can be divided in two parts, 137200 and 28, that multiplied together give a square (3841600 = 1960²).

The spelling of 13720028 in words is "thirteen million, seven hundred twenty thousand, twenty-eight".