20447156 has 12 divisors (see below), whose sum is σ = 35814660. Its totient is φ = 10214400.

The previous prime is 20447131. The next prime is 20447159. The reversal of 20447156 is 65174402.

It can be written as a sum of positive squares in 2 ways, for example, as 1175056 + 19272100 = 1084^2 + 4390^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20447159) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6260 + ... + 8948.

It is an arithmetic number, because the mean of its divisors is an integer number (2984555).

Almost surely, 2^20447156 is an apocalyptic number.

It is an amenable number.

20447156 is a deficient number, since it is larger than the sum of its proper divisors (15367504).

20447156 is a wasteful number, since it uses less digits than its factorization.

20447156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4594 (or 4592 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 20447156 is about 4521.8531599334. The cubic root of 20447156 is about 273.4498168340.

The spelling of 20447156 in words is "twenty million, four hundred forty-seven thousand, one hundred fifty-six".