20163240 has 48 divisors (see below), whose sum is σ = 65531700. Its totient is φ = 5376768.

The previous prime is 20163239. The next prime is 20163271. The reversal of 20163240 is 4236102.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19342404 + 820836 = 4398^2 + 906^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27645 + ... + 28364.

Almost surely, 2^20163240 is an apocalyptic number.

20163240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20163240 is an abundant number, since it is smaller than the sum of its proper divisors (45368460).

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

20163240 is a wasteful number, since it uses less digits than its factorization.

20163240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56026 (or 56019 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 20163240 is about 4490.3496523099. The cubic root of 20163240 is about 272.1782640545.

Adding to 20163240 its reverse (4236102), we get a palindrome (24399342).

The spelling of 20163240 in words is "twenty million, one hundred sixty-three thousand, two hundred forty".