20447136 has 36 divisors (see below), whose sum is σ = 58147362. Its totient is φ = 6815616.

The previous prime is 20447131. The next prime is 20447159. The reversal of 20447136 is 63174402.

It can be written as a sum of positive squares in only one way, i.e., 20250000 + 197136 = 4500^2 + 444^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (20447131) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35211 + ... + 35786.

Almost surely, 2^20447136 is an apocalyptic number.

It is an amenable number.

20447136 is an abundant number, since it is smaller than the sum of its proper divisors (37700226).

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

20447136 is a wasteful number, since it uses less digits than its factorization.

20447136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71013 (or 71002 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 20447136 is about 4521.8509484502. The cubic root of 20447136 is about 273.4497276774.

It can be divided in two parts, 2044 and 7136, that added together give a triangular number (9180 = T₁₃₅).

The spelling of 20447136 in words is "twenty million, four hundred forty-seven thousand, one hundred thirty-six".