20625280 has 128 divisors (see below), whose sum is σ = 55349280. Its totient is φ = 7299072.

The previous prime is 20625277. The next prime is 20625299. The reversal of 20625280 is 8252602.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 307807 + ... + 307873.

Almost surely, 2^20625280 is an apocalyptic number.

20625280 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 20625280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27674640).

20625280 is an abundant number, since it is smaller than the sum of its proper divisors (34724000).

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

20625280 is a wasteful number, since it uses less digits than its factorization.

20625280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 20625280 is about 4541.5063580270. The cubic root of 20625280 is about 274.2415686228.

Adding to 20625280 its reverse (8252602), we get a palindrome (28877882).

The spelling of 20625280 in words is "twenty million, six hundred twenty-five thousand, two hundred eighty".