20628240 has 160 divisors (see below), whose sum is σ = 69209856. Its totient is φ = 5068800.

The previous prime is 20628233. The next prime is 20628247. The reversal of 20628240 is 4282602.

It is an interprime number because it is at equal distance from previous prime (20628233) and next prime (20628247).

It is a super-3 number, since 3×20628240³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 20628240.

It is not an unprimeable number, because it can be changed into a prime (20628247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 204190 + ... + 204290.

Almost surely, 2^20628240 is an apocalyptic number.

20628240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20628240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34604928).

20628240 is an abundant number, since it is smaller than the sum of its proper divisors (48581616).

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

20628240 is a wasteful number, since it uses less digits than its factorization.

20628240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177 (or 171 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 20628240 is about 4541.8322293982. The cubic root of 20628240 is about 274.2546870905.

The spelling of 20628240 in words is "twenty million, six hundred twenty-eight thousand, two hundred forty".