20725756 has 24 divisors (see below), whose sum is σ = 37603440. Its totient is φ = 9988992.

The previous prime is 20725753. The next prime is 20725769. The reversal of 20725756 is 65752702.

It is a happy number.

It is a super-3 number, since 3×20725756³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20725753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11680 + ... + 13336.

It is an arithmetic number, because the mean of its divisors is an integer number (1566810).

Almost surely, 2^20725756 is an apocalyptic number.

It is an amenable number.

20725756 is a deficient number, since it is larger than the sum of its proper divisors (16877684).

20725756 is a wasteful number, since it uses less digits than its factorization.

20725756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1773 (or 1771 counting only the distinct ones).

The product of its (nonzero) digits is 29400, while the sum is 34.

The square root of 20725756 is about 4552.5548870936. The cubic root of 20725756 is about 274.6861698167.

The spelling of 20725756 in words is "twenty million, seven hundred twenty-five thousand, seven hundred fifty-six".