20487744 has 42 divisors (see below), whose sum is σ = 58726070. Its totient is φ = 6829056.

The previous prime is 20487743. The next prime is 20487763. The reversal of 20487744 is 44778402.

It can be written as a sum of positive squares in only one way, i.e., 20358144 + 129600 = 4512^2 + 360^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 20487699 and 20487708.

It is not an unprimeable number, because it can be changed into a prime (20487743) 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, 17209 + ... + 18360.

Almost surely, 2^20487744 is an apocalyptic number.

20487744 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20487744 is an abundant number, since it is smaller than the sum of its proper divisors (38238326).

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

20487744 is a wasteful number, since it uses less digits than its factorization.

20487744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35587 (or 35574 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 36.

The square root of 20487744 is about 4526.3389179336. The cubic root of 20487744 is about 273.6306316376.

The spelling of 20487744 in words is "twenty million, four hundred eighty-seven thousand, seven hundred forty-four".